Conditional

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Clause

Looking at the words themselves will help to keep this subject painless. A clause is simply a chunk of a sentence that has its own subject and verb and can stand alone as a complete sentence. The following sentence will become a clause when combined with another clause; this will be the “main clause.”

“We are going to the zoo.”

Conditional Clause
“Conditional” indicates an “if” or a circumstance that needs to be met. Conditional clauses are often called “if clauses.” With the “if,” the following examples are not proper sentences and are waiting to be added to a main clause.

“If it is not raining”
“If we leave soon”
“If I had looked behind me”

Conditional Sentence

Before we go to the zoo, we need to make sure the weather is cooperating, otherwise we will not go. The main clause relies on the conditional clause that was just tucked onto the front of the sentence.

“If it is not raining, we are going to the zoo.”

We will continue with the “if clause” at the front of each sentence, just for simplicity, but they can change places: “We are going to the zoo if it is not raining.”

First, Second, Third Conditional

There are three types of conditional clauses. First conditional is likely to happen and is in future tense. Second conditional is unlikely or nearly impossible and in future tense. Third conditional is impossible because it is in past tense.

“If it stops raining, we can go to the zoo.”
“If I had some money, we would go to the zoo.”
“If it had not rained all day, we would have gone to the zoo.”

The first has a pretty good chance; that rain is likely to stop at some point.

The second is unlikely because the conditions are remote, but there is still a slim chance; the speaker is broke, but perhaps he will find some money hidden away in his sock drawer or in his winter coat. Second conditional is also useful when writing about dreams or a situation nearly impossible to fulfill, such as winning the lottery or becoming a famous musician.

The third is in the past and now impossible; you cannot change yesterday.

Modal Verbs in Conditional Sentences

Those strange little modal verbs are useful in conditional sentences. Should you need a refresher, examples of modals are may, will, can, might, could, must, would, should and shall. They can be found on both sides of the comma, in both the result and the condition, and they are used in both real and unreal scenarios.

First conditional (possible): “If he can help you, he will do a great job.”
Second conditional (not likely): “If I should have to swim the Atlantic, I will probably drown.”
Third conditional (impossible): “If the chickens would have stayed awake, they would have heard the fox.”

Some modals can be ornery. Are there any modal verbs that seem like they may not work in all three types of conditional clauses?

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