believe,think,suppose,guess,hope,expect,imagine,be afraid等动词用于简略回答中,后接so来替代肯定分句,用not来替代否定分句.
注意：believe,think,suppose,guess等用于否定回答时,既可以说I don’t believe (think,suppose guess) so,也可以说I believe (think,suppose guess) not,但用hope,expect,be afraid作否定回答时,只能说I hope (expect) not以及I’m afraid not.
而且在hink,imagine,believe三词的否定答语中,用don't think/imagine/believe so比用not更为常见.