How time flies! Three years really a short time.A. isB. areC. wasD. were

问题补充：

How time flies! Three years really a short time.

A. is

B. are

C. was

D. were

答案：

(答案→)A. is

B. are

C. was

D. were

解析：三年的时间很长表示的是一个事实，用一般现在时，时间视为单数，故本题填is，选A。