重点讲解：
1. give birth
生（孩子）；分娩；生育；
eg. Mrs White gave birth to a fine healthy baby at her late thirties.
怀特太太在她将近四十岁时生了个漂亮的健康婴儿。
eg. Women do more than just give birth.
女人做的不仅仅是生儿育女。
2. serve as
用作；可当…使用；充作；
eg. Such stories serve as a spur to children's imagination.
这类故事能激发儿童的想像力。
eg. They drafted him to serve as their delegate.
他们选派他作他们的代表。
3. step in
介入，干预，插手（棘手问题）；
eg. If they step in where they're not wanted, they'll get their noses put out of joint.
如果他们介入与他们无关的事，会有人阻止他们的。
eg. There are circumstances in which the State must step in to protect children.
有些情况下，国家必须出面保护儿童。
4. make sure
一定要；设法保证；
eg. You have to make sure you're comparing like with like.
你必须确保是在进行同类比较。
eg. Screen off her bed and make sure she's not disturbed.
将她的床用屏风隔开，以确保她不受任何干扰。
5. would-be
想要成为…的；
eg. I met her first when I was a very young would-be musician.
我初次见到她时，我还是个一心想成为音乐家的十分年轻的人。
eg. There are many would-be actors and actresses in Hollywood.
在好莱坞有许多想要成为男女演员的人。
