1.（Walking on the street）,I came across one of my old friends.
在大街上散步时,我碰巧遇到了一位老朋友
2.（Unless invited）,he won't come
除非被邀请,他才会来
3.（Considering his age）,he does it better.
考虑到他的年龄,他做的还不错
4.（If more time provided）,Iwould do it better.
如果给更多时间,我会做得更好
5.（Seeing from his behaviors）,he is a gentleman.
从他的举止上看,他是一个绅士
6.You（should have made good use of the opportunity）but you gave it up
你本应该好好利用这个机会,你却放弃了
7.You can only be sure of（what you own）at present;you can't be use of something （you will get）in the future你只能拥有现在的东西,对将来得到的东西却不能有十足的把握
8.I wonder（if you could help me with my English）我想知道你是否可以帮助我学习我的英语呢
9.（Not until three days did）he come back
过了三天之后他才回来
10.It was（until she took off her sunglasses）that I realized she was famous film star
直到她摘掉墨镜,我才意识到她是个著名的影星
11.I just wonder（what it is ）that makes him so excited
我就是想知道是什么让他如此兴奋
这些都是很常考的一些用法,最好多看看语法书,对你以后考试啥的都有好处.
希望对你有所帮助~