Vitamin C helps our bodies make a special chemical, which __________ affects our brains, making us feel happy.
| A．in all | B．in turn |
| C．in advance | D．in short |
The little boy, out of curiosity, _______ the toy to see how it worked, but couldn’t put it together.
| A．took apart | B．broken down |
| C．burst into | D．knocked off |
These tax laws, which are intended for domestic companies, do not ________ to foreign companies.
| A．contribute | B．submit |
| C．lead | D．apply |
----- Your mother won’t agree with you on that, you know, this hairstyle is not suitable for a student.
----- _______? I don’t care what she thinks. Anyway, I am not a child any more.
| A．How come | B．What for |
| C．How so | D．So what |
It was some time _____ Tony realized that he had made a serious mistake on that matter.
| A．since | B．before |
| C．when | D．that |
I don’t think Jim saw me; he ______ into space.
| A．just stared | B．was just staring |
| C．has just stared | D．had just stared |