Question

They (know) answer? Did they Know Did they knew They knew

Answer 1

Did they know answer?

Правило: Past Simple. Используется Did, didn't.

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Можно лучший?

Answer 2

Ответ:

Did they know the answer?

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Past Simple.

Answer 3

The correct form is: "They knew."

The other options are not grammatically correct:

• "They (know) answer?" is incorrect because it uses the present tense "know" instead of the past tense "knew."
• "Did they Know" is incorrect because "Know" should be in the past tense, which is "knew," when used in a question with "Did."
• "Did they knew" is also incorrect for the same reason; "knew" is the correct past tense form.