There are many trees on side of the street and of the trees is still growing.A. both; th

问题补充：

There are many trees on side of the street, and of the trees is still growing.

A. both; the number

B. either; the number

C. both; a number

D. either; a number

答案：

A. both; the number

(答案→)B. either; the number

C. both; a number

D. either; a number

解析：句意：街道两边有许多树，并且树的数量仍在增长。Both两者都，后跟复数名词；either两者中的任何一者，后跟单数名词。The number of…的是数量，作主语时谓语动词用第三人称单数式；a number of许多，修饰复数名词。所以选B。