Weare watching TV we caught sight of a friend of ours . A. as soon asB. whileC. whenD. on

问题补充：

Weare watching TV we caught sight of a friend of ours .

A. as soon as

B. while

C. when

D. once

答案：

A. as soon as

B. while

(答案→)C. when

D. once

解析：可联系答.案.网客服索取。