He was about to tell me the secret someone patted him on the shoulder.A. asB. untilC. whi

问题补充：

He was about to tell me the secret someone patted him on the shoulder.

A. as

B. until

C. while

D. when

答案：

A. as

B. until

C. while

(答案→)D. when

解析：考查固定结构。Be about to do sth when…正要做某事在这时出现了意料之外的事情。句意：他正要告诉我那个秘密在这时有人拍了他的肩膀。