seem的基本用法如下:
sb/sth seem (to be) + 名词/形容词/介宾等
sb/sth seem + to do sth / to be doing sth / to have done sth
it seem + that / as if / as thought从句。
如:
He seemed (to be) unhappy.
= It seemed that he was unhappy.
She seems to be sleeping now.
She seems to have been there before.
It seems as if it is going to rain.
不过有seem to be done这种用法。
如:He seemed to have been bitten by a bee.
他看起来似乎被蜜蜂咬过。