There is some doubt Mr Zhang will sign the contract with us.A. whenB. whetherC. ifD. that

问题补充：

There is some doubt Mr Zhang will sign the contract with us.

A. when

B. whether

C. if

D. that

答案：

A. when

(答案→)B. whether

C. if

D. that

解析：考查doubt的用法。doubt用于肯定句时用whether引导同位语从句；用于否定句时，用that引导。例如：There is no doubt that...“......是毫无疑问的。”；There is some doubt whether he will come.。本题k肯定句，故用that，句意张先生会和我们签订这份协议时毫无疑问的。