this is the first time

在正式英语里,这个句子是错误的。This is the first (second, third...) time 这个结构要求后面使用现在完成时, This was the first (second, third...) time 这个结构要求后面使用过去完成时。例如:

1. This is the fourth time she's rung you in a week. (Gronin) 这是她一周内第四次给你打电话。

2. It was the second time he had been out with her alone. (London) 这是第二次他单独跟她外出。

3. That was the first time I had left England's shores. (Pollitt) 这是我第一次离开英国海岸。

4. It was not the first time I had said this, nor would it be the last. (Hillary, Living History)

这不是我第一次说这些话，也不会是最后一次。（希拉里，《亲历历史》）

但是，在美国英语里，也有人在从句里使用一般过去时：

It was the first time I knew we could do well in New Hampshire. (B. Clinton, My Life) 我头一次知道我们在新罕布什尔州能有所获。(《我的生活》)

当主句为将来时(It/This/That will be the first time...)时,从句的谓语动词要用将来完成时,但用现在完成时来代替:

1. It will be the first time that I haven't been abroad. 那将是我第一次不呆在国外。

2. Don't forget, it will be the first time I have spoken in public. 不要忘了,那将是我第一次在公众中讲话。

3. This will be the first time I have visited China. 这将是我第一次访问中国。

此外,还可以采用 It was the first time of somebody's doing sth. 的结构:

It was the first time... of her ever hearing him refer to the period of his suffering. (Dickens) 这是她第一次听到他谈论他受苦的时期。