二零一一年一月十七号的问题

Todays questions to be getting on with 

1) How do I talk about periods of time i.e. I did something for some amount of time.  e.g. I drove for 3 hours.

2) Seperable verbs seem to be getting me.  I've noticed a number of times on my journal.  How do I identify these? Does it work for every two sylable verb?

3) Is it usual to talk about people in numbers.  My new book has three people looking for a girl but it refers to them as 三个人 all the time rather than 他们。

4）Do you have any suggestions for sentence patterns I should focus on in my journal.  I started this week with

A 离 B <distance>的地方 and played with that a bit I'd like to keep doing that and add more.