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

下列各句中，没有语病的一项是（ ）

In the past 50 years, under the leadership of the CPC, the situation of Tibet has___________much better than it used to.

－My parents our home for a few hours when I arrived. I didn’t meet them.－You could call them if you wanted to know where they were.

There is a great deal of evidence _______ that musicactivities engage different parts of the brain.