The nervous look on his face suggested that he_when he has asked about the case.
问题描述：
The nervous look on his face suggested that he_when he has asked about the case.
A must lie
B is lying
C should lie
D was lying
答
选d,意思：他脸上紧张的表情表明他在被问到这个事情时说谎了.
这里suggest 是表明而不是建议的意思,所以不用虚拟语气（should +v原形）