【问】 My sister____her shorthand ability by taking notes in shorthand during lectures.

A. keeps on B. keeps up

C. keeps in D. keeps with

keep on与keep up都作“continue”、“not stop”(继续)解。这一点可以从下面的两道托福题得到证明：

(1) To keep on doing something is to____.

A. stop doing it B.refrain from doing it

C. continue doing it D. avoid doing it (TOEFL教程)

(2) To continue to do something is to keep it____.

A. up B. on C.along D. around (TOEFL.71.1;75. 2;75.5)

为什么上面的试题只能选B(keeps up)，而不能选A(keeps on)?

【答】 虽然keep on与keep up都可作“继续”解，但是，在这个意义上，keep on之后总是跟分词(doing sth.)，而keep up之后总是跟名词(keep up sth.)，例如：

1. A string broke，but the pianist kept on playing. (LDPV)

一根琴弦断了，但是这位钢琴家继续演奏下去。

2. He just kept on hitting the boy although I told him to stop. (同上)

尽管我叫他停手，他还是继续打孩子。

3. I'm glad that you are keeping up your studies. (LDPV)

我很高兴你在坚持学习。

4. If only I'd keep up my German，I might have got that job in Berlin. (ODCIE)

要是我继续学习德语的话，那我也许得到柏林的那个职务了。

5. Well done! Keep up the good work! (LDPV)

干得好!继续好好干下去吧!