We visited the factory ________ makes 80 percent of the toys in the city.
| A．where | B．there  |
C．in which | D．which |
In most western countries, on April Fool’s Day, people often play __ ___ trick on each other; children especially have great ______ fun.
| A．a; a | B．the; the | C．/; a | D．a; / |
－I’m thinking of the test tomorrow. I’m afraid I can’t pass this time.
－_________! I’m sure you’ll make it.
| A．Go ahead | B．Good luck | C．No problem | D．Cheer up |
Competitors are allowed to take a five-minute break every hour to eat，drink or do ________ is necessary
| A．which | B．that | C．where | D．what |
So far, all of the infected people are thought _______ the flu after direct contact with sick birds.
| A．to have caught | B．having caught | C．to catch | D．being caught |
A number of high buildings have arisen ______ there was nothing a year ago.
| A．when | B．where | C．before | D．until |