Unless, As long as, and Provided/Providing (that)

UNIT 39  Unless, as long as, and provided/providing (that)

A.   Unless
Study this example situation:
Joe is always listening to music lf you speak to him normally, he can't hear you. If you want him to hear you, you have to shout.

Joe can't hear unless you shout.
This means: "Joe can hear only if you shout," Unless means except if. We use unless to make an exception to something we say.

Here are some more examples of unless:

• Don't tell Ann what I said unless she asks you. (= except if she asks you)
   
• I'll come tomorrow unless I have to work. (= except if I have to work)

• I wouldn't eat between meals unless I were extremely hungry. (= except if I were extremely hungry)

We often use unless in warnings:

• We'll be late unless we hurry. (= except if we hurry)

• Unless you work harder, you're not going to pass the exam (= except if you work harder) 

•  The thief said he would hit me unless I told him where the money was. (= except if I told him)

Instead of unless it is possible to say if . . . not:

• Don't tell Ann what I said if she doesn't ask you.

• We'll be late if we don't hurry.

                        
B.   As long as     provided (that)      providing (that)
These expressions mean but only if:

• You can use my car as long as (or so long as) you drive carefully. (= but only if you drive carefully)

• Traveling by car is convenient provided (that) you have somewhere to park. (= but only if you have somewhere to park)

• Providing (that) she studies hard, she should pass the exam. (= but obly if she studies hard)

C.   When you are talking about the future, do not use will with unless, as long as, provided, or providing. Use a present tense:

• We'll be late unless we hurry. (not unless we will hurry)

• Providing she studies hard (not providing she will study)