I wrote a letter of complaint and the airline has promised to the matter.A. look upB. lo

问题补充：

I wrote a letter of complaint, and the airline has promised to the matter.

A. look up

B. look into

C. look through

D. look for

答案：

A. look up

(答案→)B. look into

C. look through

D. look for

解析：考查动词短语辨析。Look up查找；look into调查；look through浏览；look for寻找；句意：我写了一封投诉信，航空公司允诺调查此事。