4.1 The Error-Identification Method

TOEFL ITP Assessment Series Exam

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1 Test Overview, Scoring, and Strategy

1.1 What the TOEFL ITP Is and Who Takes It 1.2 How TOEFL ITP Scores Work 1.3 General Test-Taking Strategy

2 Listening Comprehension

2.1 Listening Comprehension Overview 2.2 Part A: Short Conversations 2.3 Part B and Part C: Longer Conversations and Talks 2.4 Idioms, Functions, and Common Traps

3 Grammar Foundations (Structure and Written Expression I)

3.1 Structure and Written Expression Overview 3.2 Subject-Verb Agreement 3.3 Verb Tenses and Forms 3.4 Nouns, Articles, and Determiners 3.5 Pronouns and Reference

4 Grammar in Depth (Structure and Written Expression II)

4.1 The Error-Identification Method 4.2 Parallel Structure and Word Order 4.3 Word Forms and Derivation 4.4 Prepositions and Collocations 4.5 Clauses, Conjunctions, and Comparisons

5 Reading Comprehension

5.1 Reading Comprehension Overview 5.2 Main Idea, Detail, and NOT/EXCEPT Questions 5.3 Vocabulary-in-Context Questions 5.4 Reference, Inference, and Cohesion Questions 5.5 Reading Strategies and Pacing

6 Vocabulary and Final Preparation

6.1 Building Academic Vocabulary 6.2 High-Yield Grammar Review 6.3 Exam Day and Study Plan

4.1 The Error-Identification Method

Key Takeaways Explain This Topic AI

Error-identification items (roughly questions 16-40 of Level 1 Section 2) underline four parts of one sentence labeled A-D; exactly one part is grammatically wrong and the other three are correct.

The error is always a hard grammar error, never a matter of style, word choice, or how 'natural' the sentence sounds, so an awkward-but-legal phrase is never the answer.

Use a fixed scanning order: verbs (agreement and tense) first, then word form, then parallelism, then pronouns, then articles and prepositions last.

The most frequent single error type is subject-verb agreement broken by an intervening phrase that hides the real subject (e.g., 'the list of items are').

Because the error lives inside an underlined, labeled part, you can confirm your answer by changing only that part and rereading the sentence.

Last updated: June 2026

What the Error-Identification Part Tests

The Structure and Written Expression section of the TOEFL ITP (Test of English as a Foreign Language, Institutional Testing Program) Level 1 test has 40 questions in 25 minutes (Level 2 has 25 questions in 17 minutes). The section splits into two item types. Earlier we covered sentence completion; this chapter deepens the second type, error identification , which is roughly questions 16 to 40 on Level 1.

Quick Answer: Each error-identification item is one sentence with four underlined parts labeled A, B, C, and D . Exactly one part contains a grammatical error and the other three are correct. Your job is to find the one wrong part — and the error is always grammatical, never stylistic .

The Grammatical-Not-Stylistic Rule

This rule decides many close calls. The test never asks you to judge whether a sentence is elegant , formal enough , or the way a native speaker would phrase it . It asks only whether a part breaks a hard rule of standard written English — agreement, verb form, word form, parallelism, pronoun reference, an article, or a fixed preposition. If an underlined part sounds a little clumsy but follows every rule, it is not the answer. Conversely, a part can read smoothly and still be wrong (for example, the list ... are sounds fine to the ear yet breaks agreement).

The Recommended Scanning Order

Guessing randomly among A-D wastes time. Instead, scan the underlined parts in a fixed priority order , from the error types that appear most often to those that appear least:

Verbs — check subject-verb agreement and verb tense/form first; these cause the most errors.

Word form — is the underlined word the right part of speech (noun vs. adjective vs. adverb)?

Parallelism — look at anything joined by and , or , or a correlative pair; the joined items must match in form.

Pronouns — check number agreement with the antecedent and clear reference.

Articles and prepositions — usually the smallest underlined words; check a/an/the and fixed verb/adjective + preposition pairs last.

A helpful memory hook is "Verb - Word - Parallel - Pronoun first" : the four highest-yield checks, in order, before you drop to the small function words.

The Hidden-Subject Agreement Trap

The most common single error type separates a subject from its verb with an intervening phrase so the verb seems to agree with the nearer noun. In The box of new tools are heavy , the true subject is box (singular), not tools ; the verb must be is . The fix: mentally delete prepositional phrases ( of... , in... , along with... , as well as... ) before checking agreement, because such phrases never contain the subject.

Error Type to Spotting Guide

Error type How to spot it Original example (error in bold)

Subject-verb agreement Delete the phrase between subject and verb, then check number The shipment of books arrive today. (need arrives )

Wrong verb tense/form Check time words; after a modal or 'to,' use the base verb She has began the project. (need begun )

Wrong word form Ask: is a noun, adjective, or adverb needed in this slot? He answered the question correct . (need correctly )

Faulty parallelism Compare items joined by 'and,' 'or,' or a correlative The plan is cheap, fast, and saves energy . (need energy-saving )

Pronoun agreement Match the pronoun to its antecedent in number Each member paid their dues. (need his or her )

Article error A singular count noun usually needs a/an/the She works as nurse . (need a nurse )

Preposition error Memorize fixed verb/adjective + preposition pairs The result depends of the data. (need depends on )

Redundancy Look for repeated meaning that is grammatically wrong They returned back to class. (delete back )
Worked Error-Identification Example

Item: The (A) variety of insects found in the rainforest (B) are truly remarkable, and researchers (C) continue to (D) discover new species each year.

Apply the scan order. Start with verbs . The first verb is are in part B. What is its subject? Strip the intervening phrase of insects found in the rainforest and the subject is variety , a singular noun. A singular subject needs the singular verb is , so part B is the error. Parts C and D ( continue , discover ) agree correctly with the plural researchers , and the noun variety in part A is fine. The answer is B — and the agreement check came first precisely because verbs are the highest-yield place to look.