Conditional Clauses. (If clause)
A conditional sentence describes the condition that is necessary for a particular result to occur. A situation that might possibly happen and what its results might be. ‘If’ is used to mention about events and situation that happen often or in future or that could have happened in the past but did not happen as it was expected or that are unlikely to happen at all.
Basic Types of Condition.
The Conjunctions:
If
Even if
When
Whenever
Whether
Unless
The meaning of a conditional sentence determines which verb tense needs to be used in the independent and subordinate clause.
Types of conditional sentences
Factual Conditional (zero conditional)
Conditional sentences are used to express a general or habitual fact. They can have both verbs in the present tense or past tense. In this type of conditional sentence, the verb tense in each clause is the same.
Example: If you don’t brush your teeth, you get cavities.
In the past, if people wanted something, they saved up for it.
(Here tense is same in both clauses.)
Predicative condition (Type I)
Predications about future or express future intention or possibilities.
The subordinate clause – A present tense verb.
Main clause – The modal (can, may, might, should or will) with stem verb.
Prediction: If I win the lottery, I can go to Paris.
Intention: If I win the lottery, I will go to Paris.
Possibility: If I win the lottery, I might go to Paris.
Hypothetical conditionals.(Type II)
Use conditional sentence to speculate about the future result of a possible but unlikely condition in the present.
Subordinate clause – Past tense verb
Main clause – Modals (would, could, might) + verb.
Speculation: If I won the lottery, I would go to Paris.
Unlikely present condition: If I won the lottery
Future result: I would go to Paris.
Subordinate clause should be in past tense and the main clause should be with modal verbs.
Counterfactual conditional.(Type III)
Use conditional sentence to speculate about the past result of a condition that happen in the past.
Subordinate clause: Past perfect tense
Main clause: Modal (would have, could have, might have) + past participle.
Speculation: If I had won the lottery, I would have gone to Paris.
Type IV
Untrue past condition & untrue result.
If I had cleaned the house, I could have gone to the movie.
Use conditional sentences to speculate about the future result of a condition that is not true in the present.
Subordinate: Past- tense, verb-were
Main clause: Contains modal would, could, might + the base verb.
Speculation: If I were prime minister, I would do a great job.
Untrue condition: If I were prime minister
Future result: I would do a great job
Speculation: If I were going to Paris, I would bring my passport.
Untrue condition: If I were going to Paris
Future result: I would bring my passport