“If I will be a girl, I think I will be a slut.”
Okay. So the sentence above is wrong in so many levels, especially in grammatical sense.
The sentence above is an example of a conditional. Conditionals are sentences expressing factual implications or hypothetical situations and their consequences. They are so called because the validity of the main clause of the sentence is conditional on the existence of certain circumstances, which may be expressed in a dependent clause or may be understood from the context.
A full conditional sentence (one which expresses the condition as well as its consequences) therefore contains two clauses: the dependent clause expressing the condition, called the protasis; and the main clause expressing the consequence, called the apodosis. An example of such sentence (in English) is the following:
If I have enough money, I will go to London.
Here, the condition is expressed by the clause “If I have enough money,” this being the protasis; while the consequence is expressed by “I will go to London,” this being the apodosis. (The protasis may either precede or follow the apodosis; it is equally possible to say “I will go to London if I have enough money.”) In terms of logic, the protasis corresponds to the antecedent, and the apodosis to the consequent.
In the English language, there are three main types of conditional sentences; they are simply called First, Second, Third Conditionals. In addition to these, there is also the zero condition and the mixed conditionals. Each type of conditionals has its own pattern of construction and function.
“Zero conditional” refers to conditional sentences that express a factual implication, rather than describing a hypothetical situation or potential future circumstance. The term is used particularly when both clauses are in the present tense; however such sentences can be formulated with a variety of tenses/moods, as appropriate to the situation:
If you spend too much every time, you become broke.
If the alarm went off, there’s a fire somewhere in the area.
If you are going to sit an exam tomorrow, go to bed early tonight!
If analgesics will cure it, I’ll take a couple before I go to bed.
The first of these sentences is a basic zero conditional with both clauses in the present tense. The last is an example of the use of will in a condition clause. The use of verb tenses, moods and aspects in the parts of such sentences follows general principles in uses of English verb forms.
The first conditional is formed this way:
If + [subject] + present tense of the verb, [subject] will + infinitive/present tense/imperative.
In the basic first conditional pattern, the condition is expressed using the present tense (having future meaning in this context), and the consequence using the future construction with will (or shall):
If you need to arrive early tomorrow, my assistant will let you know.
If they invite me, I will/shall consider their invitation carefully.
The present tense used in the condition clause may take the form of the simple present as in the above examples, or the present progressive, present perfect or present perfect progressive as appropriate.
If he is sleeping when we arrive, we shall wake him. (present progressive)
Will you wake him if he hasn’t stirred by ten o’clock? (present perfect)
If you have been working for more than ten hours when he returns, he will take your place. (present perfect progressive)
The first conditional expresses an open condition—what is said in the condition is possible. This condition refers either to present or to future time.
If you turn around, I will stab you to death.
If my mother knows about this, we are in serious trouble.
In the normal form of the second conditional, the condition clause is in the past tense (although it does not have past meaning), and the consequence is expressed using the conditional construction with the auxiliary would:
If I were a girl, I would attend a lot of parties.
If it rained today, I would dance in the street.
The past tense (simple past or past progressive) of the condition clause is historically the past subjunctive. In modern English, this is identical to the past indicative, except in the first and third persons singular of the verb be, where the indicative is was and the subjunctive were; in this case either form may be used. (Was is more colloquial, and were more formal, although the phrase “if I were you” is common in colloquial language.)
If I (he, she, it) was/were rich, there would be no trouble about the finances.
If I (he, she, it) was/were speaking, you would not dare cut in.
When were is the verb of the condition clause, it can be used to make an inverted condition clause without a conjunction. If the condition clause uses the past tense of another verb, it may be replaced by the auxiliary construction was/were to + infinitive (particularly if it has hypothetical future reference); if this is done and were is used, then, inversion can be applied here:
If I was a boy, . . . / If I were a boy, . . . / Were I a boy, . . .
If I knew, . . . / If I was/were to know, . . . / Were I to know, . . .
Another possible pattern is “if it wasn’t/weren’t for . . . ” (inverted form: “were it not for . . . ”), which means something like “in the absence of . . . .”
The conditional construction of the main clause is usually the simple conditional; sometimes, the conditional progressive (would be waiting) is used. Occasionally, with a first person subject, the auxiliary would is replaced by should (similarly to the way will is replaced by shall). Also, would may be replaced by another appropriate modal: could, should, might.
When referring to hypothetical future circumstance, there may be little difference in meaning between the first and second conditional (factual vs. counterfactual, realis vs. irrealis). The following two sentences have similar meaning, although the second (with the second conditional) implies less likelihood that the condition will be fulfilled:
If you leave now, you will still catch your train.
If you left now, you would still catch your train.
Notice that in indirect speech reported in the past tense, the first conditional naturally changes to the second:
She’ll kill me if she finds out.
He said I would kill him if I found out.
The second conditional expresses unreal (impossible) or improbable situations.
These conditions are in the present. The tense is past, but we are talking about the present.
If I knew her name, I would tell you. (I do not know her name now, so I cannot tell you.)
If I were you, I would tell my father. (I am not you, and will never be you.)
If I become president, I will change the social security system. (Said by a presidential candidate; there is a possibility of him winning the election.)
If I became president, I would change the social security system. (Said by a schoolboy: improbable.)
If we win this match, we are qualified for the semifinals.
If I won a million pounds, I would stop teaching. (improbable)
Here the condition clause is in the past perfect, and the consequence is expressed using the conditional perfect.
If you had told me, I would have helped you.
Would he have won the race if I had helped him?
The condition clause can undergo inversion, with omission of the conjunction:
Had you told me, I would have helped you.
Would he have won the race had I helped him?
Another possible pattern is “if it hadn’t been for . . . ” (inverted form: “had it not been for . . . ”), which means something like “in the absence of . . . ”, with past reference.
In the main clause, the auxiliary would can be replaced by could, should or might, as described for the second conditional.
If only one of the two clauses has past reference, a mixed conditional pattern is used.
This pattern is used to refer to hypothetical situations in a past time frame, generally counterfactual (or at least presented as counterfactual, or likely to be counterfactual).
If you had warned me, I would not have told your father about that party.(But you didn’t, and I have).
Am ixed conditional usually refers to a mixture of the second and third conditionals (the counterfactual patterns). Here, either the condition or the consequence, but not both, has a past time reference.
When the condition refers to the past, but the consequence to the present, the condition clause is in the past perfect (as with the third conditional), while the main clause is in the conditional mood as in the second conditional (i.e. simple conditional or conditional progressive, but not conditional perfect).
If you had done exactly what I told you, we wouldn’t be in this mess now.
If I hadn’t married Josh, I wouldn’t be living in Paris now.
When the consequence refers to the past, but the condition is not expressed as being limited to the past, the condition clause is expressed as in the second conditional (past, but not past perfect), while the main clause is in the conditional perfect as in the third conditional:
If we were soldiers, we wouldn’t have done it like that.
Other variations on the respective clause patterns are possible, as used accordingly in the second and third conditionals.
Other Useful Things to Remember
1. The conditional construction does not normally use will or would in if-clauses. However, an exception can be made if will or would express willingness, as in requests, they can be used in if-clauses.
If you will please follow me, the manager will see you now.
I would be grateful if you would help me with my homework.
2. For the second conditional, were usually replaces was:
If I were a girl . . .
3. Instead of if not, we can use unless.
I’ll be back tomorrow unless there it rains.
He’ll help you with your homework unless you act like a total mean girl.