imperatives ad naseum

[david-us.livejournal.com]

I still have a question about Russian imperatives. I don't seem to detect any pattern in selecting the imperfective or the perfective form of the verb when using an imperative.

It seems to me that Russians prefer the imperfective form when issuing a negative command and tend to use the perfective when issuing a positive command.

Which is more correct?

Открой дверь!  или   Открывай дверь!

Would it be correct to say "Не открой дверь!", or, must you say, "Не открывай дверь!" ?

David Emerling
Memphis, TN

Russian numbers?

[cassiemorre.livejournal.com]

Sorry but on my phone so I can't use the russian letters.

Well I was wondering, with numbers, when do they change.

For example, odeen can also be raz when used in a certain way.

When do these number changes occur?

Thank you