Jack almost fell off a big tree while climbing it but managed to until help came. A. put

问题补充：

Jack almost fell off a big tree while climbing it, but managed to until help came.

A. put on

B. hang on

C. turn on

D. take on

答案：

A. put on

(答案→)B. hang on

C. turn on

D. take on

解析：本题考查动词短语辨析。句意：爬树时杰克差点掉下从大树掉下来，但尽力坚持到救助到来。hang on坚持下去；等候；紧紧抓住。