I think you should be about giving your address to strangers. It might be dangerous.[ ]

1Jim couldn’t understand how themachine worked until his friends____ how to use it.

It is reported that up to now, mountain slides have cut off more than ten villages from the outside world,_____ more than 100 hundred people alive and _____ many houses [ ]

______do you improve your speaking skills—-By _____ with groups.

What kind of person do you want to helpyou—______ always trying his best and nevergiving up in time of difficulty.