Playing on a frozen sports field sounds like a lot of fun. Isn't it rather risky, ____?

My uncle's house in the downtown area is much smaller than ours，but it is twice________expensive.

In the good care of the nurses , the boy is          recovreing from his heart operation .

The lively boy suddenly appeared to be ________ quiet, so his mother knew something unusual must have happened.

It turned out that his pulse beats ____ , which made us relieved.