【学习难点】：
1．参加 be in =take part in 参加会议，参加群众活动
We’ll take part in the meeting later.
They will take part in climbing hills.
2．be sure相信 对……有把握,肯定
I am sure of /about the match
He is sure to win
I am sure (that) he will come.
3．It’s my first time to do sth.这是我第一次做。。。。。
