单项选择题
A. When compared B. When comparing C. Compare D. Comparing
Had electronic computers not been invented, many proble...
单项选择题Had electronic computers not been invented, many problems of space flight（）now.
A. could not have been solved B. could not be solved C. must not be solved D. should not have been solved
There has been a decrease（）the number of students enter...
单项选择题There has been a decrease（）the number of students entering the Medical College this year.
A.on B.over C.in D.of
His use of technical terms let his audience（）A. confusi...
单项选择题His use of technical terms let his audience（）
A. confusing B. confused C. with confusion D. to confusion
