Question

Since then the number of people taking driving lessons ________________ 20%.

A. has increased to

B. increases by

C. has increased by

D. have increased by

 

Answer 1

答案：C
提示：

since then与完成时连用，不能选择B项；the number of people做主语，谓语动词用单数，故D项不可选；20%表示“差额”，即增减程度，应用by，故答案选C。 increase可用作及物或不及物动词，意为“增加、提高”。例如： As young men, we should try to increase our knowledge. 作为年轻人，我们应尽力增长知识。 We want to give some money to this project so that the number of these deer in China can be increased. 我们要向这项工程捐些钱，以便使在中国的这些鹿的数量有所增加。 Our difficulties are increasing. 我们的困难正在增加。 increase to后面常跟“增长的总量”，而increase by后跟的是“差额”，即表示增减程度的词。reduce作“减少”时，和increase的这一点用法相同。例如： The number of the survivals has increased to 15. 幸存者的人数已增至15人了。 The average income of each family in China has increased by 10. 5 percent this year. 今年中国家庭的平均收入增长了10. 5%。 increase也可作名词，意为“增长；增加”，后面常加介词in，表示“在……方面的增长”。例如： The introduction of the new technology has brought an increase in production. 新技术的引进带来了产量的增加。 There has always been an increase in our population. 我们的人口一直在增长。