----Martin Murray used to be afraid of alone----But now he realizes that his mother is

问题补充：

----Martin Murray used to be afraid of alone.

----But now he realizes that his mother is always there for him.

A. is

B. was

C. be

D. being

答案：

A. is

B. was

C. be

(答案→)D. being

解析：

试题分析: 句意：马丁.穆雷过去常常害怕孤独。但现在他意识到他的妈妈一直在那儿陪他。used to过去常常做某事，be afraid of 害怕，后接动名词，故选D