Complete the Words

What the task looks like

Complete the Words is the first of the three Reading tasks. You see a short academic paragraph of about 70–100 words. The first sentence is complete. After it, the second half of every second word is missing, and you type the missing letters. Each paragraph has 10 words to complete (ETS, Updated TOEFL iBT Test Overview; TOEFL iBT Lesson Plans: Reading). ETS's blueprint lists 30 Complete the Words items in the Reading section, each worth one point (ETS, 2026 Test Blueprint and Specifications).

Here is a short original illustration of the pattern. Underscores show how many letters are missing, and the bold numbers label the blanks:

Many desert plants store water in thick leaves. Their sur____ (1) is of___ (2) covered wi__ (3) a waxy layer that slows evaporation.

The answers are surface (missing face), often (missing ten) and with (missing th). Notice three things:

• the damage begins with the second word of the second sentence (Their is intact; surface is damaged);
• it then hits every second word, whatever kind of word it is: a noun (surface), an adverb (often), a preposition (with);
• you always see the first half of the word, and the number of underscores tells you how many letters are missing.

In this course, a word with an odd number of letters keeps the shorter first part: surface (7 letters) shows sur and hides face; often (5 letters) shows of and hides ten. ETS's published example follows the same pattern.

What the task measures

ETS's blueprint describes the skill as processing academic written text "for meaning and form": using word-order rules, vocabulary knowledge and reading comprehension to build meaningful text (ETS, 2026 Test Blueprint and Specifications). In practice, every blank tests three things at once:

1. Meaning. Which word makes sense in this paragraph?
2. Grammar. Which form fits this slot: noun or verb, singular or plural, past or present, -ing or -ed?
3. Spelling. Can you type the rest of the word correctly? A misspelled word is a wrong answer.

You do not need to know anything about the topic: everything you need is in the paragraph (ETS, TOEFL iBT Reading Section).

A five-step method

1. Read the intact first sentence carefully. It tells you the topic and often contains words that come back later in the paragraph.
2. Read the whole damaged paragraph once, quickly. Many blanks are obvious once you know where the paragraph is going. Fill those first in your head.
3. For each blank, look left and right. What does the grammar need? After the, you need a noun or adjective. After has, a past participle. Before a noun, maybe an adjective or a determiner. Between two clauses, perhaps a conjunction.
4. Use the letters you see and the number of missing letters. bec___ with three missing letters is became or become (the tense decides), never because, which would appear as bec____ with four. Count.
5. Reread the finished sentence. Does it sound like natural academic English? Is every ending right (-s, -ed, -ly)? Then type carefully.

Worked example

Read this original paragraph. Try every blank before reading the solutions.

Mangrove forests grow along tropical coastlines where fresh water meets the sea. Their tan____ (1) roots sl__ (2) the move____ (3) of wa___ (4) and tr__ (5) sediment car____ (6) by riv___ (7). Over ti__ (8), this bui___ (9) up t__ (10) land and helps protect nearby communities from storm waves.

Blank	Answer	How you know
(1) tan____	tangled	Between Their and roots you need an adjective. Tangled (twisted together) describes roots and has exactly four missing letters.
(2) sl__	slow	The subject roots needs a present-tense verb; slow + the movement = make it slower. Slip has the right length but makes no sense with this object.
(3) move____	movement	After the you need a noun; move + ment is the noun form. Moves would have only one missing letter.
(4) wa___	water	The movement of water: the first sentence already mentioned water. Waste has the right length, but nothing in the paragraph is about waste.
(5) tr__	trap	Parallel verb after and: roots slow … and trap sediment. Same tense as slow.
(6) car____	carried	Sediment carried by rivers is a reduced passive (that is carried by); by signals the past participle. Carries would have only three missing letters and would need a subject.
(7) riv___	rivers	Plural noun after by; no article, so the general plural rivers fits. River would have only two missing letters.
(8) ti__	time	Over time is a fixed expression meaning gradually.
(9) bui___	builds	Subject this is singular, so the verb needs third-person -s: builds up. Built would need only two letters and the wrong tense.
(10) t__	the	Before land, a determiner; the land the roots have been building.

Notice that half of the answers were decided by grammar alone (movement, carried, builds, the) and the others by meaning and collocation (over time, slow the movement). The letter count settled every close call.

The words you will meet in the blanks

Because every second word is damaged, the blanks are a sample of ordinary English. Roughly two kinds appear:

Function words

Short words that hold sentences together: articles (the, an), pronouns and determiners (their, this, these, its, which), prepositions (from, into, between, during), conjunctions (because, although, while, but) and auxiliaries (has, were, can, would). They look easy, but they are where careless mistakes happen. Learn to spot them from their first letters:

You see	Likely answers	Decide by
th__	that, them, then, they, this, thus	What comes next: a noun (this, that), a clause (that), a verb (they), a sequence or result (then, thus)?
th___	their, there, these, those	Possession before a noun (their), existence before is/are (there), or a plural noun, near or far (these, those)?
wh___	where, which, while, whose	Place, thing, time or contrast, possession?
bec___	became, become	Past time (became), or after to, has or a modal (become)?
wi__	with, will, wide	Before a noun phrase (with), before a verb (will), or describing something (wide)?

Content words in families

Nouns, verbs, adjectives and adverbs, usually with a suffix in the missing half. The grammar of the slot tells you which family member you need:

Slot	Form	Example
after the, a, its	noun	the devel______ → development
after has/have/had	past participle	have incr_____ → increased
after to (infinitive)	base verb	to mea____ → measure
before a noun	adjective	a signi______ change → significant
modifying a verb or adjective	adverb	grew rap____ → rapidly

Common traps

Trap	Example	Fix
Right word, wrong form	the growth of the popul_____ → typing ate (populate)	After of the you need a noun, and five letters are missing: population.
Ignoring agreement	Each of the samples cont____ salt → typing ain	Each is singular, so the verb is contains; four letters are missing (ains).
Wrong tense	In 1850, the city bec___ a port → become	A past date needs the past: became. Both words fit the letter count, so only the grammar decides.
Losing the letter count	alth____ → typing ough plus an extra letter	Type exactly the missing letters; although hides four (ough).
Spelling	it occu____ twice → typing red	The word is occurred: double r, so four letters are missing (rred).
Plausible but unnatural word	pl__ a role → plan	Collocation: you play a role.

Always count the underscores. If the count does not match your word, your word is wrong.

Spelling patterns worth reviewing

• Doubling before a suffix: occur → occurred, begin → beginning, refer → referred, but visit → visited (stress not on the last syllable).
• Dropping silent e: produce → producing, use → usable, but notice → noticeable.
• -y to -i: study → studies, carry → carried, early → earlier.
• Common suffixes: -tion, -sion, -ment, -ness, -ity, -ance/-ence, -able/-ible, -ous, -ive, -al, -ly.
• Frequent academic words you should be able to spell without thinking: environment, government, necessary, separate, therefore, although, research, significant, process, develop.

Pacing (a suggestion)

ETS does not publish a time limit for this task alone; the Reading section as a whole takes about 30 minutes for about 50 items (ETS, Test Content and Structure). Complete the Words items are short, so work at a steady pace: aim to finish a paragraph in roughly two to three minutes, leaving more time for the passages that follow. If a blank defeats you, make your best guess from the grammar and move on; a reasonable guess costs nothing.

How to practise

• Do the practice set in this lesson, then the Complete the Words paragraphs in this course's practice test.
• Make your own. Take any well-written paragraph (a university news article, an encyclopedia entry), copy it, and remove the second half of every second word after the first sentence. Come back the next day and restore it. Check spelling exactly.
• Study word families, not single words: analyse, analysis, analytical, analytically. The language-skills lessons on academic vocabulary and grammar show you how.
• Use ETS's free practice tests for the updated test to see the real on-screen format (ETS, Full-Length Practice Tests 1 and 2, linked from the course page).

Check yourself

• Where in the paragraph does the damage start, and how many words are damaged?
• What do the underscores tell you, and why should you always count them?
• After the, after has, after to and before a noun: which forms do you expect?
• You see wh___ (three letters missing) before a noun clause about a place. What is the word?
• Why is occured marked wrong even though the meaning is right?
• What is the last thing you do before moving to the next blank?