问题补充：
It is the second time that I in Beijing
A. am
B. was
C. have been
D. had been
答案：
A. am
B. was
(答案→)C. have been
D. had been
解析：考查固定句型。这是我第二次去北京了。It is the second time that have/has done.某人第几次做某事了。It was the second tome that had done .某人第几次做某事了。注意两个句型的不同，如果是is,用现在完成时。如果是was 要用过去完成时。一定要分清楚。
考点考查固定句型
