It was not until dark( )he found( )he believedwas the correct way to solve the problem

问题描述:

It was not until dark( )he found( )he believedwas the correct way to solve the problem
A.that;that B.that;what C.when;what D.when;that
该题正确答案应选B,说明其他几项为什么不对,

not until 强调句型It be adj +that从句 C和D排除
he believed从句缺少宾语,用what