Seem是不及物動詞嗎？

seem 是「連綴動詞」，屬於不及物動詞的一種，又稱「不完全不及物動詞」。

連綴動詞後面必須接「補語」，否則句意就不完整。像原句如果只有 It seems. 意思只有（似乎），似乎什麼呢？必須有東西來補充，才知道句子究竟要說什麼。這裡 that 就是引導一個子句來做「主詞補語」。

說話者若要說 It seems to be the case that...... 也可以，意思一樣，但在英語語法的分析上，主詞補語是不定詞片語 to be the case，而 that 的子句成了 case 的同位語。

It seems that--(no need to be the case in this complement in apposition));
seem=verb intransitive;=have or give the impression,appearance of being or doing; appear to be;
eg:-It seems that no one knew what had happened in that case.
eg:-I seem unable to get out=I can't seem to get out.
It would seem that I can't get out-----is a cautious way of saying "It seems that "I can't get out."
eg:-It would seem that I've been out in the rain from my wet clothes.So it seems" I've been out once."
"seems"---eg:-It seems that---
eg:-The book seems quite interesting.
eg:-There seems to be no objections to her proposal.She seems to think so.What seems easy to some people seems hard to others.I shall act as seems best=I shall act as it seems best to me to get rid of her.
"seeming"adj.--apparent but perhaps not real;
eg:-In spite of his seeming friendship he gave me no money or help.
"seemingly" adv. means in appearance; apparently