重点讲解：
1. in a jiffy
很快；瞬间；
eg. He conjured up a whole meal in a jiffy.
他一眨眼功夫就变出了一桌饭菜。
eg. We will do it in a jiffy.
我们马上去做。
2. just a moment/minute
等一下；且慢；
eg. Just a moment. Let me mark down your name and address.
等一下，让我把你的姓名和地址记下来。
eg. Just a minute, I have to fix my hair.
等会儿，我得整整头发。
3. get a move on
快点；抓紧点；
eg. We'd better get a move on before it rains.
我们最好在下雨之前赶快做。
eg. Tell Harry to get a move on.
叫哈里快些！
4. a space of time
一段（时间）；期间；
eg. They've come a long way in a short space of time.
他们在很短的时间之内就大老远地赶了过来。
eg. It was all over in a relatively short space of time.
不一会儿工夫就完全结束了。
5. be sure of
一定的；必定的；无疑的；确保的；
eg. Since you are so sure of it he'll believe you.
既然你对此这么有把握，他会相信你的。
eg. I'm not too sure of it.
这件事我不太有把握。
