These type of clauses are often called "if clauses" in English grammar books and follow conditional sentence patterns. Take a look at the chart below to study the various usage of different time expressions.
When an adverb clause begins the sentence use a comma to separate the two clauses. Example: If he comes, we will have some lunch.. When the adverb clause finishes the sentence there is no need for a comma. Example: He would have invited me if he had known.
- If we win, we'll go to Kelly's to celebrate!
- She would buy a house, if she had enough money.
'If' clauses express the conditions necessary for the result. If clauses are followed by expected results based on the condition. More information on the correct tense usage for the conditionalsEven if
- Even if she saves a lot, she won't be able to afford that house.
In contrast to sentences with 'if' sentences with 'even if' show a result that is unexpected based on the condition in the 'even if' clause. Example: COMPARE: If she studies hard, she will pass the exam AND Even if she studies hard, she won't pass the exam.Whether or not
- They won't be able to come whether or not they have enough money.
- Whether they have money or not, they won't be able to come.
'Whether or not' expresses the idea that neither one condition or another matters; the result will be the same. Notice the possibility of inversion (Whether they have money or not) with 'whether or not'.Unless
- Unless she hurries up, we won't arrive in time.
- We won't go unless he arrives soon.
'Unless' expresses the idea of 'if not' Example: Unless she hurries up, we won't arrive in time. MEANS THE SAME AS: If she doesn't hurry up, we won't arrive in time. 'Unless' is only used in the first conditional.In case (that), in the event (that)
- In the case you need me, I'll be at Tom's.
- I'll be studying upstairs in the event he calls.
'In case' and 'in the event' usually mean that you don't expect something to happen, but if it does... Both are used primarily for future events.Only if
- We'll give you your bicycle only if you do well on your exams.
- Only if you do well on your exams will we give you your bicycle.
'Only if' means 'only in the case that something happens - and only if'. This form basically means the same as 'if'. However, it does stress the condition for the result. Note that when 'only if' begins the sentence you need to invert the main clause.
More Adverb Clauses