"Have you known" or "Did you know"?
55425
Tense for an event that occurs as you read it
4548
“have found” vs. “found”
13947
Simple past or present perfect?
97408
Interpreting having known
152893
inform about vs inform of
20222
"Can you please" vs. "Could you please"
20314
"Do you know where's Linda?" vs "Do you know where Linda is?"
90495
Have lived vs. Have been living
92285
I asked + present/past tense
122849
When do you use “learnt” and when “learned”?
60477
Is the past tense correct in "Did you know Fred was a doctor?"
119136
"done" vs "have done"
82433
What did you say / said?
19551
'What are you?' vs. 'What do you do?'
25348
Use "does" in front of another verb in a question?
4246
When to use "this" or "that"?
144014
either + singular + 'have' or 'has'?