英语语法问题seems to be doing sth

seem to do (表示常态) It seems to rain.似乎要下雨了.
seem to be doing sth 看起来正在做 He seems to be doing his homework.他看似正在做作业.
seem to have done 看似做完了 He seems to have done his homework.他看似已经做完作业了.
seem 有3个结构 注意区分 同用法的还有pretend,happen,etc