What's happening to Tom?He_____.A)sounds sadly B)seems sadly C)sounds sad D)seems sad

答案选择：D
seem可用作连系动词,、“主语+ seem +（to be ）+表语”,表语多为名词或形容词,有时是其他的词或短语,以说明主语的特征或状态.
Tom seems （to be ） a very clever boy.汤姆看上去是一个非常聪明的男孩.
The man over there seems to be a new teacher.那边的那个人看上去像一个新老师.
在英语中,有：
look(看起来）sound(听起来）smell（闻起来)等,是表示感官的系动词,后接形容词充当表语.
Although his mother is 50 years old,she looks very young.