Rewrite the sentence with adj + to + v: The machine/ difficult/use
Rewrite the sentence with adj+to+v
4.The machine/ difficult /use
6.I/ surprised/get /his letter/yesterday
8.The question is very difficult .I can't understand it
9.Don't go near the pond.It's dangerous
10.Get up early and do the exercise regularly.It is healthy
11.Tell him the news immediately.It is very important