单项选择题
A．sense B．opinion C．use D．program
How many more decades will have to pass （） scientists s...
单项选择题How many more decades will have to pass （） scientists succeed in providing a cure for cancer？
A．when B．before C．since D．until
After 15 years in the United States, he has finally dec...
单项选择题After 15 years in the United States, he has finally decided to （） American citizenship.
A．concentrate on B．apply for C．look out for D．appeal on
The disease beri-beri （）．A．kills large numbers of Easte...
单项选择题The disease beri-beri （）．
A．kills large numbers of Eastern peoples B．is a vitamin deficiency （缺乏） disease C．is caused by diseased deer D．can be caught from diseased chickens
