【doubt的用法Idoubt____shewillchangehermindforsheoftenbehavesstrangely.这一题我觉得应该是选that,答案却是whether,为啥?啥时改用that,啥时用whether,在意思上有区别么?还有doubt和suspect的区别是啥?】

　　doubt的用法

　　Idoubt____shewillchangehermindforsheoftenbehavesstrangely.

　　这一题我觉得应该是选that,答案却是whether,为啥?

　　啥时改用that,啥时用whether,在意思上有区别么?

　　还有doubt和suspect的区别是啥?