1、had better (not) do sth. 最好（不要）做某事
①You’d better give up smoking.It dose no good to your health.
②she had better not come this evening. 今晚她最好不要来。
2、hand down(=pass down) 相传、传给
In poor families, clothes may be handed down from one child to the next.
短语：hand back 把……归还…… ；hand in 面交，提出；
hand out 分发；hand on 传阅，依次传递；hand over 移交。
(1)happen to do sth.(主语常为“人”)，意为“碰巧、恰好”。
to 后可用不定式的一般式to do，完成式to have done进行式to be doing。如：
You happened to be out when I came to your house. 我到你家时，你正好出去了。She happened to have just finished reading the book. 碰巧她刚刚读完那本书。The two salesmen happened to be quarrelling when the manager entered.
(2)It (so) happen tha t…“（如此）碰巧，恰好”。如：
It happens that he is a teacher of English. 恰好他是位英语老师。
It so happened that he was going that way too. 如此碰巧的是他也往那边走。
注意：句型(1) 和(2) 可互换，如：
I happened to have no money with me./It happened that I had no money with me.
(3)happen to sb./sth.“某人/物出事，发生了……情况”。
如：What has happened to your hand? 你的手怎么了？
Be careful not to let anything happen to that child. 小心别让那个孩子出任何事。
①—We haven’t heard from Jane for a long time.
—What do you suppose __________to her?
②They happened to _______for Tianjin when we got there.
③If anything __________you,let me know.
A.is happened to
Key:①C ②B ③D