Why Do Students Keep Forgetting English Vocabulary?

The problem may not be memory. It may be the words, the method, or the lack of meaningful use.

Parents often tell me:

“My child studied these vocabulary words, but now they have forgotten all of them.”

The student may have passed a test, matched the words with their translations, or correctly answered a multiple-choice exercise. A few weeks later, however, the student cannot explain the words, recognize them in a new context, or use them independently.

This does not necessarily mean the student has a poor memory.

Students often forget vocabulary because they do not meet or use the terms often enough. They may study a word for one test and then have no reason to think about it again.

A useful rule is:

If you repeatedly want or need to use this term, you are much more likely to learn it.

A student who needs English to play a game, understand a story, discuss an interesting subject, or speak with another person will encounter useful terms repeatedly. Each new encounter strengthens the connection between the term, its meaning, and its use.

A random word on a test may receive no such reinforcement.

A Word and a Term Are Not Always the Same

Before continuing, I make a small distinction in my lessons:

A word is always one word.

A term may contain one word or several words.

For example:

• assuage is one word and one term.
• high-frequency word is a three-word term.
• take something for granted is a multiword expression.

This distinction matters because vocabulary learning involves more than memorizing individual words. Students must also learn useful phrases, combinations, and relationships between words.

Build Your Own Flashcards

One method I often recommend is for students to make their own flashcards.

Creating the card is already part of the learning process. The student must decide what the term means, what kind of clue will help, and how the term can connect with something memorable.

I recommend a simple version of the waterfall method.

Divide the cards into three piles:

• Easy
• Medium
• Hard

Then choose how much time is available:

• One minute
• Five minutes
• Ten minutes or more

Begin with the difficult cards. Answer each card before turning it over.

When an answer becomes quick and accurate, move the card toward the easier pile.

When the answer is wrong, incomplete, or very slow, keep it in the harder pile.

Continue reviewing difficult cards more often while occasionally checking that the easy cards are still easy.

The purpose is not merely to finish the entire stack. Ask:

How many cards can I answer correctly and independently during the time I have?

A student can complete a one-minute review when busy or a longer review when preparing for a lesson. A short review is still useful when it requires the student to recall the answer rather than merely reread it.

More Than One Kind of Flashcard Can Work

Students do not need to use the same flashcard design for every term.

Instead of asking, “What permanent type of learner am I?” a better question may be:

What kind of clue will help me remember this particular term?

1. Use a picture

Concrete terms are often easiest to learn visually.

For the term ladder, the student might place a drawing or printed picture on one side and the term on the other.

This works especially well for:

• Objects
• Animals
• Places
• Actions that are easy to illustrate
• Visible adjectives
• Position and movement

The student can also add a question:

What can you do with it?

Answer: You can use a ladder to climb to a higher place.

The picture establishes the meaning, while the question encourages the student to use the term.

2. Use an easy fact-based question

The front of the card can contain a simple question that clearly leads to the target term.

Front:

What do you use to climb onto a roof?

Back:

A ladder.

Another example:

Front:

What do we call a person who designs buildings?

Back:

An architect.

These questions are useful because students must retrieve the term from its meaning. They are not simply looking at the word and recognizing it.

3. Use a silly or memorable connection

A strange, funny, or personal connection can make a difficult word easier to remember.

Whenever I think of the word assuage, I think of sausage. The words are not related in meaning, but they sound similar enough to create a memorable connection.

My silly question might be:

Why do you want a sausage?

My silly answer could be:

Because a sausage will assuage my hunger.

Then I would include the real definition beneath it:

assuage (vt.): to make an unpleasant feeling, pain, worry, or problem less strong

Example:

A warm meal helped assuage his hunger.

The funny connection helps retrieve the sound of the word. The definition and example establish its actual meaning.

The silly clue should lead toward accurate knowledge. It should never replace the definition.

One of the Biggest Problems: Random Vocabulary Lists

One of the most common problems I see is a long list of random words and idioms that students supposedly “need” to memorize.

The terms may not have been chosen according to:

• The student’s current English level
• How commonly the terms appear
• Their usefulness in real communication
• The current reading or lesson
• The student’s interests and needs
• Whether the student is ready to use them

Or any reason at all. I have talked with Chinese and bilingual teachers who have no knowledge of the CEFR framework. They do not know why students are learning these words, sentence frames, or questions at this point. I encourage every parent or student learning English to ask, “Why are we learning this right now?” Accept only strong, logical answers.

When there is no clear reason why the student is learning a particular term at that point in their development, this creates several problems.

The terms may be:

• Rare
• Difficult to pronounce
• Difficult to explain
• Far above the student’s level
• Unconnected to one another
• Far removed from the student’s real life
• Unlikely to appear again soon

When a student cannot imagine wanting or needing a term, there is little reason for it to remain active.

The student may remember it long enough for one test. They may not.

Kids are so busy and they have so much to do right now. It can be very easy for them to make room for new information by deleting old information that’s not important.

Why I Teach Idioms Sparingly

Idioms are an especially difficult area.

English contains an enormous number of idioms. Some are common and useful. Many others are regional, generational, old-fashioned, highly informal, or limited to particular situations.

An idiom that sounded clever or fashionable years ago may rarely appear today. A student can spend considerable time memorizing an expression that they may never hear in a real conversation.

For this reason, I teach idioms sparingly.

I would rather help a student master a high-frequency word or broadly useful phrase than memorize a colorful expression with very limited value.

This does not mean that idioms are worthless. Common idioms can improve reading and listening comprehension. However, they should be selected because students are genuinely likely to encounter them—not merely because an idiom list was easy to find.

How I Choose Vocabulary

I choose vocabulary according to level, frequency, usefulness, and relevance to the lesson.

One important resource behind my vocabulary system is what I have often called the BCWFF. Its official name is the British Council Word Family Framework, usually shortened to WFF.

The WFF is a searchable resource containing more than 22,000 vocabulary items arranged across the six CEFR levels, from A1 to C2. It also organizes related members of word families, helping teachers see how vocabulary develops as students advance.

The CEFR is an internationally used framework that describes language ability from A1 beginner level through C2 proficiency.

Why should parents care about this?

Because students should not receive vocabulary lists based only on someone’s personal guess about what sounds difficult or impressive.

A level-based framework gives us a more reliable starting point:

• Is this term appropriate for the student’s current level?
• Is it normally learned much earlier or later?
• Does the student already know the more basic members of its word family?
• Is this the best use of limited study time?

The framework does not replace teacher judgment. A term may be above the student’s normal level but still important for a particular story, subject, test, or personal need.

However, it is much better to begin with level, frequency, and usefulness than with a random list.

Two Large Groups of Vocabulary Terms

In my lessons, vocabulary terms generally fall into two broad groups:

• Picture terms
• Terms that require definitions

Picture terms

Picture terms are concrete enough to teach visually.

A student can see the picture, hear the pronunciation, say the term, and begin answering targeted questions about it.

Common questions include:

• What can you do with it?
• Where is it?
• Why do they have it?
• Why is it important?
• Do you want it? Why?
• How is X different from Y?
• What would happen if X happened instead of Y?
• What adjectives can describe it?
• What prepositions can describe its position?
• What sensory details can you add?

A picture makes the first meaning easier to establish, but the questions are what help the student move beyond simple recognition.

It is not enough to point at a picture and name it once. Students should connect the term with actions, features, locations, comparisons, purposes, and personal opinions.

Terms that require definitions

Abstract terms cannot always be shown clearly in one picture.

These terms need:

• A simple definition
• A part-of-speech label
• Clear pronunciation practice
• A natural example sentence
• Questions that test understanding
• Opportunities to use the term in new contexts

My definitions always use more common words to explain harder terms.

After learning the definition, students answer questions about the terms. Every question is targeted to reveal key details about the terms. These questions make students explain, compare, predict, describe, and apply greater meaning to each term.

This prevents vocabulary study from becoming a simple English-to-Chinese matching exercise.

Four Vocabulary Review Exercises I Use Regularly

Introducing a term is only the beginning. Students then need several kinds of review.

I use four recurring vocabulary review formats because each one requires a different kind of thinking.

1. Fill in the Blank

In a Fill-in-the-Blank exercise, the student chooses the best vocabulary term to complete a sentence.

Each sentence contains enough information to identify one clear answer.

For example:

The warm soup helped ________ her hunger after the long journey.

Answer: assuage

A strong Fill-in-the-Blank question does not depend on guessing, a picture from another page, or information hidden elsewhere. The sentence itself provides the necessary context.

This exercise works well because it asks:

• Does the student understand the meaning?
• Can the student identify when the term fits?
• Can the student distinguish it from the other words in the word box?
• Does the completed sentence sound natural?

Fill in the Blank exercises are fine and useful, but it is still a controlled exercise. The student is choosing from available answers rather than independently producing the term.

That is why it should not be the only form of review.

2. Combining Ideas

In a Combining Ideas exercise, students see four pictures and a list of today’s vocab terms. The idea is for students to make their own sentences with two or more recently learned vocabulary terms. Students can and should use the pictures to make their own original sentences in ways that demonstrate understanding of the terms. Students can describe just one picture, or combine the ideas of multiple pictures to make their sentences.

For example:

The architect used an innovative design to conserve energy in the new building.

Instead of studying architect, innovative, conserve, and energy as four unrelated items, the student sees how they can work together in one meaningful idea.

These sentences should:

• Make sense in the real world
• Use the terms logically, naturally, and appropriately.

Avoid “word salad.” This is when a sentence has a lot of random vocab words without clearly showing understanding of any terms. For example: “I feel indignant and skeptical because the barricade proposed to wither with hospitality.” That sentence might be “grammatically” correct, but it makes no sense and clearly does not show understanding of any of the terms.

The exercise also gives students practice in speaking and creative writing. The more terms they can use in a sentence, the better practice they get.

3. Staying True

In a Staying True exercise, students replace a target term with a synonym, broader category, or closely related expression while keeping the sentence true and natural.

For example:

A robin often lives near gardens.

A student might replace robin with the broader term bird, and the sentence would remain true:

A bird often lives near gardens.

However, not every possible replacement works. We cannot really replace “animal” with any other term because animal is already a foundational word. There is no word easier than animal. We can describe it and give examples of it, but no other word is easier than animal.

Staying True helps students understand that knowing a term includes understanding its relationship with other terms.

Students practice:

• Synonyms
• Broader categories and hypernyms

4. Vocabulary Relationships Review

The goal of Vocabulary Relationships Review is to help students build their own strong dictionary-style definitions.

Students examine how a target term connects with other words. Each relationship reveals a different part of its meaning. Students then express these relationships through clear sentence frames and combine the information into a complete definition.

Useful sentence frames include:

• A is a kind of B.
• A is a way of doing B.
• A has B in it.
• A is a part of B.
• A is the opposite of B.
• All As are Bs.

Students also learn several advanced terms for describing vocabulary relationships.

Synonyms

Synonyms are words with similar meanings.

huge :: big, enormous

All huge things are big.

The meanings are similar, although they may not be perfectly interchangeable in every sentence.

Antonyms

Antonyms are words with opposite meanings.

polite :: rude

Polite is the opposite of rude.

Knowing an opposite can help students understand the boundaries of a term’s meaning.

Attributes

Attributes are qualities or features commonly connected with a term.

crowded :: many people, little space

A crowded place has many people in it.

The attributes explain what normally makes something crowded.

Hypernyms

A hypernym is a broader category that contains the target term.

architect :: professional

An architect is a kind of professional.

The word professional is broader than architect. Architects belong to that larger category.

Hyponyms

A hyponym is a more specific example within a broader category.

smartphone :: device

A smartphone is a kind of device.

Device is the broader category. Smartphone is one specific kind of device.

Troponyms

A troponym is a specific way of performing an action.

whisper :: speak

Whispering is a way of speaking.

Whispering is not simply related to speaking. It describes a particular way of speaking.

Sister Terms

Sister terms are terms that share the same broader category.

dentist :: doctor

All dentists and doctors are health professionals.

A dentist is not a kind of doctor in every use of the word, and a doctor is not a kind of dentist. However, both belong to the broader category of health professionals.

Meronyms

A meronym is a part of something larger.

sentence :: paragraph

A sentence is a part of a paragraph.

The sentence is one component within the larger whole.

Holonyms

A holonym is the whole that contains another term as one of its parts.

bicycle :: wheel

A bicycle has wheels in it.

In this relationship, wheel is the meronym, while bicycle is the holonym.

Collocates

Collocates are words that commonly appear together.

decision :: make, difficult, final

Common combinations include:

• Make a decision
• A difficult decision
• A final decision

Students should not only know what decision means. They should also know that English speakers normally make a decision rather than do a decision.

Building a Definition for “Persuade”

Students can now examine several relationships around the target term persuade.

• To persuade is a way of influencing someone.
• Persuading often has reasons, arguments, or encouragement in it.
• Persuading is different from forcing.
• Common collocates include persuade someone to do something and persuade someone that something is true.

Students can combine those relationships into a definition:

persuade (vt.): to cause someone to do or believe something by giving reasons, arguments, or encouragement

They can then create an example:

She persuaded her parents to let her join the school trip.

The definition includes the broader action, the method, and the common grammatical pattern.

Building a Definition for “Obstacle”

Students can perform the same process with obstacle.

• An obstacle is a kind of barrier or problem.
• An obstacle blocks progress or makes progress more difficult.
• A physical obstacle may be a wall or fallen tree.
• A non-physical obstacle may be fear, lack of money, or lack of experience.
• Common collocates include face an obstacle, remove an obstacle, and overcome an obstacle.

Students can combine these ideas into a definition:

obstacle (n.): something that blocks progress or makes it more difficult to reach a goal

They can then create an example:

His fear of making mistakes was a major obstacle to speaking English confidently.

Why Vocabulary Relationships Review Works

A strong definition is rarely built from one translated word.

Through this exercise, students can understand terms much more deeply. Students can understand:

• Its broader category
• Similar and opposite meanings
• Important qualities
• More specific examples
• Parts and wholes
• Related terms
• Common word combinations
• How it behaves in a sentence

Instead of copying a finished definition, students construct the meaning themselves.

That process gives the term more connections in the student’s mind, making it easier to understand, remember, explain, and use later.

Why the Four Exercises Work Better Together

Each exercise tests something different:

• Fill in the Blank: Can the student recognize the correct term from context?
• Combining Ideas: Can the student understand several terms working together?
• Staying True: Can the student replace or generalize a term without changing the truth?
• Vocabulary Relationships Review: Can the student explain how terms connect?

No single exercise proves complete mastery.

No exercise can prove that a student has permanently mastered a term. A student may complete a Fill-in-the-Blank exercise correctly and still struggle to define the word, recognize it while listening, or use it during conversation.

That is why vocabulary practice should change form. Students should meet the term:

• With a picture
• In a definition
• In different sentences
• In relationships with other terms
• During reading and listening
• During speaking and writing
• Again at a later time

Each activity develops a different skill. Together, they give the student a much stronger chance of understanding, remembering, and using the term outside the original vocabulary page.

Teachers and parents can choose useful terms, explain them clearly, and provide strong practice. However, they cannot learn on the student’s behalf.

Strong teaching must be matched by strong student ownership.

Students must pay attention, retrieve the term without help, notice it when it appears, and use it repeatedly. Forgetting is not failure. It is a signal to review, adjust, and work again.

The goal is not to complete a worksheet and declare the word finished. The goal is to make the term useful.

Do the work. Use the language. Return to it when necessary. That is how vocabulary becomes part of a student’s English.