单项选择题
It was the wealth of the （） pioneer landowner John Harvard that made Harvard University possible.
A．precious B．curious C．anxious D．prosperous
单项选择题 How many more decades will have to pass （） scientists succeed in providing a cure for cancer？
单项选择题 After 15 years in the United States, he has finally decided to （） American citizenship.
单项选择题 The disease beri-beri （）．
