ENGLISH GRAMMAR
CONDITIONAL STRUCTURE of VERBS
How and when to use the four basic conditional structures.
Conditionals are sentences with two clauses: an ‘if' clause and a main clause.
Four basic conditional structures are used in English:
Conditional structures with inversion :
In conditional sentences we can sometimes replace the 'if' with an inversion:
Four basic conditional structures are used in English:
- Zero Conditional
- First Conditional
- Second Conditional
- Third Conditional
| Zero conditional | What is always true or usually happens, or what is advised in this situation. | |
| IF | +Present Simple | +Present Simple |
| If | you have a ticket | you go straight in. |
| If | you stand in the rain | you get wet. |
| If | you see an accident | call an ambulance. |
Note : The 'if' in the above sentences can usually be replaced by 'when' without changing the meaning.
| First conditional | Something that will possibly happen in the future. | |
| IF | +Present Simple | +Will + Infinitive |
| If | I see an accident | I will call a doctor. |
| If | it rains tomorrow | the picnic will be cancelled. |
| If | you make an apple tart | Dad will eat it. |
Note : Sometimes we use can or may instead of
'will'.
For example : "If you finish your vegetables, you
can have a dessert."
| Second conditional | Imaginary events that are probably not going to happen. | |
| IF | +Past Simple | +Would + Infinitive |
| If | I saw an accident | I would call a doctor. |
| If | he had more money | he would buy a new car. |
| If | she worked harder | her results would improve. |
Note : Sometimes we use could or might instead of
'would'.
For example:
"If we invited the author, he might come."
"If we ordered a larger quantity, we could ask for a reduction."
| Third conditional | Something that did not happen, and the reaction or result you imagine if it really had happened. | |
| IF | +Past Perfect | +Would + have + Past Participle |
| If | I had seen the accident | I would have called a doctor. |
| If | he had read the instructions | he would have assembled it faster. |
| If | she had stayed in Paris | she would have improved her French. |
In conditional sentences we can sometimes replace the 'if' with an inversion:
- If I had known it would be so difficult I would never have enrolled.
With inversion: → Had I known it would be so difficult I would never have enrolled. - If we had known she was alone we could have called her.
With inversion: → Had we known she was alone we would have called her.