Question

(2005·天津)

He tried his best to solve the problcm, ________ difficult it was.

[　　]

A．however

B．no matter

C．whatever

D．a(chǎn)lthough

Answer 1

答案：A
解析：

從結(jié)構(gòu)上看，填上一個詞應(yīng)使逗號后的分句成為一個狀語從句。A、C、D三項均可引導(dǎo)一個狀語從句。從意思上看應(yīng)選however。