There's a sentence in my book:

"Jack did not know why he failed in the examination."

There are two events in the sentence:
1. Failing in the examination
2. Not knowing the reason

Since event 1 occurred before event 2, why did they not use "had" in the sentence?

  • 1
    Because real people speaking English don't necessarily follow the rules in your grammar book, especially about complex tenses. "Had" is certainly possible, but it's optional: the meaning makes it clear that one event must precede the other.
    – Colin Fine
    May 16, 2017 at 21:40
  • Because you don't need to use past perfect if the order of events is clear. (You can if you want to, so had failed is also grammatical.) May 11, 2020 at 13:39

2 Answers 2


I think that's because we're focused on the action of failing and not on the result of the action of failing in the past. Make sense?


— What happened?
— Jack failed the exam!
— Why did he fail the exam?
— Because he didn't prepare for it the way he should have.

  • Yes it does make sense. Jan 19, 2017 at 5:23
  • But when the same sentence is transformed into indirect and starts with 'It was', they have used had. Given indirect speech is " It was not known to Jack why he had failed in the examination." Jan 19, 2017 at 5:27

"Didn't know" and "failed" both refer to a time that is before the present. Using "had failed" explicitly puts the failure before another past event (which might be when he did not know, or might be when the sentence is set).

Note that using "didn't know" instead of "doesn't know" outside a narrative suggests that Jack may now know, perhaps because he asked his lecturer.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .