3．用于现在完成时的常用句型 (1)It is/has been＋一段时间＋since＋一般过去时“自从……以来多久了。” (2)This/It is the first/second...time (that)＋现在完成时“这是(某人)第一/二……次做某事。” It is/has been two weeks since we arrived here. 自从我们到这里已经有两星期了。 It is the third time that I have seen the film. 这是我第三次看这部电影了。