"Do" and "Did"

[Haidt]

Hello everyone!

Sometime, I have a concern about using "Do" or "Did" in some situations, such as:
"Did you know that in English we usually don't say "good day"?"
"Do you know which lesson number this one is?"
"Do you remember what the word 'extension' means?"
...

Is there any rule for this? Please help!

Thank you very much for your attention!

Hai

[Marryk3]

hi .,
i m also a learner but for your question i've got an answer , i hope it will help u

definitely there is a rule for DO and DID

Did you know that in English we usually don't say "good day"?"
here the speaker is talking about past and asking in present,

"Do you know which lesson number this one is?"
here the speaker is asking at the present moment about the present situation.

"Do you remember what the word 'extension' means?"
remembering something is never in past.thats why it says do you remember

[Torsten]

[Haidt]

Hi Marryk3,

Thanks for your reply

but how about this question:

"Did you know that there are still active volcanoes?"
the spearker is not talking about past, is it right?
BTW, can we use "Do" instead of "Did" in this situation? If yes, is there any diference?

Thanks,
Hai

[Mister Micawber]

Did you know that there are still active volcanoes?
Do you know that there are still active volcanoes?

In this case, 'did' is more polite and more usual, because it suggests that the speaker is unsure about the listener's knowledge. Past used for present is used when statements are hypothetical. Another example: 'I haven't met Julie Roberts, but if I did, I would be very excited.'
_________________
Native English teacher at Mister Micawber's

[Marryk3]

hi hai,
m also getting confused , lol
mister micawber's reply has helped me

[Haidt]

Thanks for your help Micawber. It's really useful information for me!

Hai