now是什么时态的代表

　　I could do it now, if you like.

　　如果你愿意的话，我现在就可以做这事。

　　Now she won't have to go out to work any more.

　　现在她不必再出去工作了。

　　She'll have had the results by now.

　　她现在应该知道结果了。

　　We're used to the noise from the traffic now.

　　现在我们已经适应车辆往来的噪音了。

　　This unit is now an established part of the course.

　　这个单元现在为本课程既定的一部分。