Select the option that will improve the underlined part of the given sentence.
When I saw him, I will ask him to return the book he borrowed.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. see him.
Error concept: Sequence of tenses with time clauses
What is wrong: The sentence uses 'When I saw him, I will ask him…', which mixes past tense ('saw') with future tense ('will ask'), creating a mismatch.
Grammatical concept: When a sentence contains a time clause introduced by words like when, after, before, as soon as, and the main clause is in the future, the time clause should be in the present tense (not past or future).
Incorrectness of the concept in context: The use of 'saw' (simple past) in the time clause is incorrect because the main action ('will ask') is in the future.
It should follow: When + simple present, main clause + will + verb
How to correct: Replace 'saw' with 'see' to align the tenses properly according to the rule of future time clauses.
Correction: see him
Final sentence: When I see him, I will ask him to return the book he borrowed.