TOEFL Complete the Words is not solved by vocabulary size alone. A familiar word can still be wrong if it conflicts with the visible letters, required word class, inflection, collocation, or argument of the passage. The best completion is the one that makes all those signals agree.
ETS currently lists Complete the Words as a TOEFL iBT Reading task that measures vocabulary knowledge and meaning in context. Official overview material describes partially missing words in a short academic text. This guide uses only original examples and does not reproduce live items.
Start with the Lyra Practice TOEFL vocabulary hub, the vocabulary-in-context guide, and Complete the Words practice exercises.
Use five filters in order
- Visible form: Which letters are fixed?
- Grammar: What word class and sentence role fit?
- Inflection: Singular, plural, tense, participle, or comparison?
- Collocation: Which completion combines naturally with nearby words?
- Passage logic: Does it preserve cause, contrast, reference, and main idea?
Do not stop after the first filter that produces a real word.
Mistake 1: completing from meaning but ignoring letters
Sentence: “The species is wi_______ distributed across the northern region.”
Wrong thought: “Commonly fits the meaning.”
Repair: The visible wi and the collocation widely distributed support widely. A semantic synonym cannot override fixed form.
Always copy the visible beginning accurately before generating candidates.
Mistake 2: building a real word with the wrong word class
Sentence: “Researchers noted a subst_______ increase in seed production.”
Wrong: substantially
Correct: substantial
The blank directly modifies increase, a noun, so an adjective is required. Increased substantially would require an adverb because it modifies the verb.
Repair method: mark the slot N, V, ADJ, or ADV before completing it.
Mistake 3: ignoring the inflection
Sentence: “During the previous decade, the river frequently overfl_____ its banks.”
Wrong: overflow
Correct: overflowed
The past-time frame and singular subject require the past form. Meaning alone does not complete the grammar.
Watch for:
- plural agreement: results indicate;
- third-person singular: evidence suggests;
- participles: was measured, has increased;
- comparison: higher than, the largest.
Mistake 4: choosing the first familiar member of a word family
Sentence: “The coating improves the mater____’s resistance to moisture.”
Candidates may include material, materially, materialize. Only material’s supplies the noun plus possessive relationship before resistance.
Learn families as patterns:
- vary (verb), varied/variable (adjective), variation/variability (noun), variably (adverb);
- respond, responsive, response;
- persist, persistent, persistence.
Lyra Practice vocabulary entries can be used to build these form grids instead of studying an isolated definition.
Understanding is only the first step.
Lyra Practice helps you retrieve and use high-value workplace expressions in realistic situations until they feel natural.
Start a practice session →Mistake 5: accepting a possible meaning but missing the collocation
Sentence: “The findings ca__ doubt on the earlier explanation.”
Wrong candidate: “carry doubt”
Correct: cast doubt on
The fixed relationship controls the completion. Other academic combinations include draw a conclusion, pose a risk, reach a threshold, account for a difference, and yield a result.
Do not assume the rarest option is strongest. Natural combinations are evidence.
Mistake 6: reading only the target sentence
Mini-passage:
Early maps placed the settlement beside the coast. Later excavation, however, found building foundations several kilometers inland. This ev______ suggests that the coastline has shifted.
Wrong: event because it begins with ev.
Correct: evidence because this refers to the excavation finding, and suggests takes a singular subject.
The prior sentence establishes the referent. Read at least one sentence before and after when available.
Mistake 7: missing a contrast marker
Mini-passage:
The first trial produced only a modest improvement. Nev________, the method was retained because it required far less energy.
Wrong: Never
Correct: Nevertheless
The second sentence concedes the limited improvement and gives a separate reason for retention. Discourse markers constrain meaning:
- however/nevertheless: contrast or concession;
- therefore/consequently: result;
- moreover/furthermore: addition;
- for example: illustration;
- instead: replacement or alternative.
Mistake 8: forcing a dramatic synonym
Sentence: “The moss is prev_____ in damp, shaded locations, appearing in 42% of surveyed plots.”
Wrong: pervasive if the visible letters and measured scope point elsewhere.
Correct: prevalent.
Pervasive can imply extensive spread throughout a setting. A measured presence in 42% of plots supports prevalent more comfortably in this context, and the fixed beginning distinguishes the form.
Mistake 9: changing the passage’s claim strength
Mini-passage:
The study involved twelve ponds in one region. Its results su_____ that shaded ponds may retain water longer during dry periods.
Wrong: surely prove as a conceptual completion.
Correct: suggest.
The small regional sample and may signal limited inference. Vocabulary should preserve uncertainty rather than upgrading it.
Full worked repair
Original practice paragraph:
Urban trees can alter conditions at street level. Their lea___ provide shade, wh___ can re____ surface temperatures dur___ hot weather. How____, young tr___ need reg____ watering unt__ their ro___ systems bec___ established.
Work through the filters:
- leaves: plural subject for provide and visible lea;
- which: relative pronoun referring to shade;
- reduce: base verb after can;
- during: time relationship before a noun phrase;
- however: contrast between benefit and maintenance need;
- trees: plural modified by young;
- regular: adjective modifying watering;
- until: time boundary;
- root: noun used attributively before systems;
- become: base form agreeing with plural subject systems.
Notice that no answer comes from topic knowledge alone. Form, syntax, and discourse collaborate.
Repair your review process
Do not reread only for general meaning. Audit each completion:
- underline fixed letters;
- draw an arrow to the word it modifies;
- mark tense or number;
- box the local collocation;
- name the logical relationship to the previous sentence.
If two completions remain possible, do not invent a hidden rule. In your own practice material, revise the context until one answer is determined. Deterministic practice builds useful discrimination.
Reject ambiguous homemade items
A self-made gap is not useful merely because one answer occurred to its author. Ask another reader to complete it without seeing the key. If two words satisfy the visible letters, grammar, collocation, and passage meaning, expand or revise the context.
For example, “The policy was re______ after the review” might allow revised, rejected, or retained, depending on how many letters are hidden and what the surrounding passage says. Add a consequence—new wording was published, implementation stopped, or the original terms stayed in force—so one completion becomes necessary. The goal is not to imitate uncertainty; it is to practice coordinating form and meaning.
Keep an error log by cause
Label each miss letters, grammar, inflection, collocation, reference, connector, or claim strength. Then write one new sentence that isolates the same cause with different vocabulary. If you chose an adverb before a noun, for example, contrast “a substantial change” with “changed substantially.” This is more useful than copying the correct spelling several times because it records the decision that failed. Review the largest error category first; ten unrelated new words will not repair a repeated word-class mistake.
Practice with Lyra Practice
Choose five words from the TOEFL vocabulary hub and map each word family. Write an original 70–100-word academic paragraph, then partially delete ten words. Validate every answer with the word-families and affixes guide and complete the practice exercises. Lyra Practice content should supply the vocabulary relationships; your context should determine the answer.
Final self-check
- Did I preserve every visible letter in order?
- What word class does the sentence require?
- Does tense, number, possession, or comparison fit?
- Is the nearby collocation natural?
- What does a pronoun or determiner refer to?
- Does a connector match the passage relationship?
- Did I preserve the author’s claim strength?
- Have I read beyond the target sentence?
- Can I explain why competing completions fail?
Sources
Related
- TOEFL Vocabulary Practice
- TOEFL Complete the Words: vocabulary in context
- TOEFL Complete the Words: word families and affixes
- TOEFL Complete the Words practice
- TOEFL vocabulary list by task
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