expense n. 费用，开销，花费
[特征]
- what are the expenses of these goods?
这些商品的费用是多少？
- a new car can be a great expense.
买一辆新汽车要花很多钱。
[备考必背] 重要词组
at one's expense 由某人付款
- we were all entertained at tom's expense.
我们全由汤姆请客。
at the expense of 以……为代价
he became a brilliant scholar, but only at the expense of his health.
他成为了一位卓越的学者，却牺牲了健康。
at any expense 不管花费多少钱
- he wanted to buy the book at any expense.
不管花多少钱他都想买这本书。
explain v. 解释，说明
[特征]
- the boy was explaining to the teacher why he was late.
这个男孩正向老师解释他为什么迟到。
- please explain to me where to begin and how to do it.
请向我说明从哪里开始以及怎样做。
[考点]
①explain后面不能接the reason，这一点经常考到。
（误）can you explain the reason why you were late?
（正）can you explain why you were late?
你能解释一下为什么迟到吗？
②表示“给某人解释……”，explain后不直接接某人，也不用for，而用介词to。
（误）the teacher explained us this problem.
（正）the teacher explained this problem to us.
老师给我们解释了这道难题。
[备考必背] 派生词
explanation n. 解释，说明
- the text still needs explanation.
课文还需要被解释。
explode v. （使）爆炸，（突然）爆发
[特征]
- it's a custom to explode fireworks to celebrate the spring festival.
燃放爆竹庆祝春节是一种习俗。
- the bomb exploded near the tall building.
炸弹在这座高楼附近爆炸了。
[备考必背] 重要词组
explode with anger 勃然大怒 explode with laughter 哄堂大笑
- the audience exploded with laughter.
观众哄堂大笑。
expose v. 使暴露，使曝光，揭露
[特征]
- don't expose your skin to the flaming sun.
别把你的皮肤暴露在炎热的阳光下。
- this film has been exposed.
这片子已经曝光了。
[备考必背] 重要词组
expose ... to ... 把……暴露在……
- the company exposed the plan to the newspapers.
公司向几家报纸透露了这个计划。