A friend and I were discussing a past event and she said:
"I don't know when you left yesterday"
but I thought she ought to say:
"I don't know when you leave yesterday"
Please tell me which one is correct?
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Sign up to join this communityA friend and I were discussing a past event and she said:
"I don't know when you left yesterday"
but I thought she ought to say:
"I don't know when you leave yesterday"
Please tell me which one is correct?
Pretty sure your friend's right: leave is PRESENT tense (i.e. I don't know when you leave today), whereas left is the PAST tense of leave (i.e. I don't know when you left yesterday). Hope that helps.
The phrase "I don't know what time you left yesterday." would be better than both of those phrases.
Your second phrase is completely incorrect because it mixes a present tense with a past word form.
I leave yesterday*
This sentence is incorrect, for your present form, "leave", clashes with the past form, "yesterday".
The first sentence is heading in the right direction, yet it's the word "when" that messes up the sentence. The correct form would be:
I left yesterday.
If you want to incorporate the rest of the sentence into it, the correct form would be:
I don't know (at) what time you left yesterday.
And no offense, but if you are still learning the English language, I suggest you post this on English Language Learners