You are given a block of text which explains the theory of this concept.
Once you have read the theory, do the exercises given below to test how well you have understood the ideas.
How to do the Exercises:
You are given a set of words.
You are also given some sentences with input boxes, and you are required to use the words to complete the sentences correctly.
You can put your chosen word into the input box by first clicking on the word and then in the input box.
The word will appear in the input box.
If it is correct, it will go green, and if not, it will go red.
PET - IF, WHEN and UNLESS
IF and UNLESS are used to describe the conditions under which something can happen.
- You can go to Madrid IF you have a car.
This means the condition for you to be able to go to Madrid is to have a car.
It also means you can ONLY go to Madrid IF you have a car.
So ONLY IF is more accurate than IF on its own.
This sentence can be expressed in another way using UNLESS, but with the same meaning.
- You cannot go to Madrid UNLESS you have a car.
Notice that when UNLESS is used, GO is replaced by CANNOT GO.
- You CAN go to Madrid IF you have a car.
- You CANNOT go to Madrid UNLESS you have a car.
In such sentences, you can use IF or WHEN, but they have different meanings.
- I will call you IF I have time. (you are not sure IF you can call. It depends on you having time.)
- I will call you WHEN I have time. (you are sure you can call. It depends on WHEN you have time.)
IF is used in a similar way to WHETHER, but they have slightly different meanings.
IF suggests only one option, but WHETHER suggests two options.
- I will go to Madrid IF I have a car.
- I will go to Madrid WHETHER I have a car or not.
They have very similar meanings, but WHETHER is more correct when there are two conditions given, if not IF is fine.
Here, we have WHETHER I HAVE A CAR or WHETHER I DON'T HAVE A CAR.
Notice WHETHER is always used with OR.
IF and UNLESS are commonly used in transformation exercises.
- He will help us only IF we pay him.
- He will not help us UNLESS we pay him.