The worst tornado of all time occurred in 1925, ______ three US states.

______ right in the center of the city, the park attracts a lot of tourists.

It’s impossible for him to escape ________ this time; he made such a big mistake.

Stop_____ this kind of deer. They are_________.

________ from endless homework on weekends, the students now find their own activities, such as taking a ride together to watch the sunrise.

He was busy writing a story, only _____once in a while to smoke a cigarette.

A study ________ in the U.S.A. in 1977 showed that the chemical ASA in aspirin could prevent a stroke.
A. carrying out    B. carried out    C. working out    D. worked out

Mr Black decided to give up his farm and devote all his time to______ those children living on the streets.

The lecture hall______ by Doctor Li in the 1980s can contain at most 6,000 people.