–- Excuse me, would you mind answering a few questions?--- Well, I don’t know. I’m in a hurry _______.

You must keep it _______ in mind that education is the first productivity. 

Noise is unpleasant, _____ when you are trying to sleep．

Last night Mr. Crook didn’t come back at the usual time. __________ , he met some friends and stayed out until midnight. 

The meeting is beginning at 8 o’clock. _____, let’s make some preparations for it.