条件句和虚拟语气（5）

Question：老师，除了虚拟条件句，我们，还有其他虚拟语气要学习吗？

Answer：有的，我们今天就开始学习这类句式。条件句和虚拟语气（5） Unless, provided (that)等

条件句和虚拟语气（5） Unless, provided (that) 等（1）

Unless, provided (that)等（1）

Reading：

If you go to a foreign country , you’d better know the customs of the country to which you will go. In this way you will know how to behave politely. Here are some tips:

Men kiss each other when they meet in many countries in the world such as Russia, France, Arab countries and so on. It is good manners for an Arab to stand close to his friend when they are talking. But English people do not like to be too close to one another unless there is a reason.

In the western countries, people will not go to the party unless they are invited.

I．Unless

1．Unless=if…not

2．Unless所接的从句的动词和if所接的动词一样。不用 will或 would。

People will not go to the party unless they are invited.

(不说 unless they will be invited.)

此句也可以说成：People will not go to the party unless invited.

3．下列句式不可以用unless代替if not：

虚拟条件：If he weren’t so stupid, he would understand.

尚未发生的事情的后果：I’ll be angry if I’m not invited to the party.

小练习1： 用unless改写句子：

1 You can’t go hang-gliding if you aren’t 16 orover.

2 If you haven’t got a medical certificate, you can’t go scuba diving.

II．As long as, provided (that)/providing (that)

Reading：

Rosanna Fisher works at an outdoor activities centre on the west coat of Scotland.

Two young people are asking Rosanna if they can do certain things.

“Can I go into town this evening ,Rosanna ?”

“Yes, provided that you go with a friend, and as long as you get back by 10.30 p.m.”

“Will it be safe to got windsurfing this afternoon ?”

“Yes. You’ll be OK providing there’s an instructor with you and as long as you don’t go too far out to sea.”

1 用 provided/providing(that) 或as long as表示条件，语气比if 强，意即 only if

As long as和provided/providing (that)的意义相同 ，所接的从句的动词和if所接的动词一样。 

You can go into town, provided that go with a friend.

(= You can go, only if you go with a friend.)

You’ll be OK, as long as you don’t go too far out to sea.

(=You’ll be OK, only if you don’t go too far out to sea.)

2．在 provided和providing后面经常省略that。

You’ll be OK, providing there’s an instructor with you

(You’ll be OK, providing that there’s an instructor with you.)

小练习II：用 as long as 或 provided/providing (that)完成句子：

1.Mark can go windsurfing… there(be) enough wind.

2.Emily can go into town …(get back) late.

上期答案：

I 1 He could have gone back to London on the airline bus  2 He might have noticed her.

II 1 If he hadn’t met her, he’d still be living in London now.  2 If she hadn’t dropped her pen, he wouldn’t know her now.  3 If he hadn’t picked her pen up ,  he wouldn’t be here with her now.