There are lots of flowers on sides of the street.A. each B. eitherC. allD. both

问题补充：

There are lots of flowers on sides of the street.

A. each

B. either

C. all

D. both

答案：

A. each

B. either

C. all

(答案→)D. both

解析：each每一个；either两个中任何一个；all所有都；both两个都。句意：在大街的两边有许多花儿。结合语境可知此处指的是两者都，故选D。