There’s some litter on the floor. Please .A. pick up itB. pick it upC. pick them upD. pick

问题补充：

There’s some litter on the floor. Please .

A. pick up it

B. pick it up

C. pick them up

D. pick up them

答案：

A. pick up it

(答案→)B. pick it up

C. pick them up

D. pick up them

解析：句意：地板上有一些垃圾，请把它捡起来。结合语境可知下文人称代词指的是前文的不可数名词litter，故用单数形式，选B。