1.if
2.unless=if...not
3.as long as=so long as
4.as(so) far as
5.in case
6.whether...or
7.provided that
8.once
9.on condition that
10.supposing
1.You will fail unless you work hard.
=You will fail if you don't work hard.
如果你不努力工作，你就会失败。
1.unless=if...not(not须在谓语处)
2.unless最好的翻译为：如果......不
2.Whether she was playing in the streets
or on a count,she was a fierence competitor.
无论她在大街上还是在球场上踢球，她都是一个不要命的比赛者
whether...or可以和either...or互换吗？
不可以！道理很简单，whether引导句子，而either不引导句子
3.I will agree to go to provided that my expenses are paid.
假如为我负担费用，我就去
4.You can go out on condition that you wear an overcoat.
只要你穿上一件大衣，你就可以出去
