1.drop by 顺便拜访

When men reach the age of 30, their testosterone levels drop by one to two per cent every year.
男子在30岁后，他们睾丸激素水平每年要下降百分之一到百分之二。

This year Britain's nominal GDP-the value of the combined contribution of output and inflation-will actually drop by some 3-4%.
今年英国名义上的国内生产总值（指产出和通货膨胀综合作用的价值）实际上将下降3%-4%。

2.take over 接管；接收

He will take over Class 9801 next week.
下星期他将接管 9801 班。

Johnson took over the chairmanship of the committee yesterday.
约翰逊昨天接任委员会主席一职。

3.need to 需要

You need to touch up the poem.
你需要给这首诗润色一下。

Do we need to discuss this question?
这个问题还用得着讨论吗?

4.pledge to 保证

He would keep his pledge to the utmost of his power.
他将极力信守他的誓言。

In the Second Training we pledge to practice generosity and not support social injustice and oppression.
在第二项训练中，我们保证，实践宽宏大量，不支持社会不公正和压迫。