121. be certain of (=be sure of) 有把握, 一定

a) We are certain of victory. 我们一定会获得胜利。

122. for certain (=for sure )肯定地,有把握地

a) Some soils are actually too alkaline for certain plant life.

123. by chance(=accidentally, by accident)偶然

a) They met by chance on a plane.

b) 他们在飞机上不期而遇

124. for a change换换环境(花样等)

a) ate early for a change. 变化一下提早吃饭

125. in charge of (=responsible for) 负责(某事)

a) Who's in Charge of this Network?

126. take charge of (be responsible for)负责管理(照顾)

a) She is the youngest manager who takes charge of the overseas business in the company.她是这个公司里负责海外业务最年轻的经理。

127. charge…for 因…索取(费用),charge sb with sth 控告某人犯有…

a) Charges ten dollars for a haircut.

128. round the clock(=all day and all night, usually without stopping) 昼夜不停地

a) This is a terrific mission and we are very busy doing science round the clock.

129. comment on sth评论

a) Everyone commented on her new hat.

b) 大家都在评论她的新帽子。

c) He commented on the bad road.

d) 他评论这条糟糕的路。

130. commit oneself to致力于

a) I commit myself to strive for grades of "C" or better in all my high school classes and to benefit fully from the classes offered during the summer program.