He had to pause from time to time to wipe the sweat from his forehead，because the air-conditioning system __________.
| A．broke in |
| B．broke up |
| C．broke out |
| D．broke down |
We found ___ for us to finish the work within two days.
| A．it impossible | B．that possible | C．this impossible | D．possible |
Professor Smith ___ China yesterday.
| A．arrived at | B．arrived in | C．get go | D．reached for |
I’m writing to you and ask whether you’d like to give us ___ how to learn English.
| A．some advice on | B．some advices about | C．an advice about | D．advices on |
I wonder why he hasn't __ any of my letters for such a long time.
| A．replied | B．replied to | C．answer for | D．asked |
--Look! John is ___. Let’s go and see if he needs any help.
A, out of the breath B. out of breath C. out of his breath D. out of breathes