UNIT
20
Zero and first conditionals; time clauses
• IF clauses are sentences that present a situation or condition that may lead to a result: if clause (condition) ➝ main clause (result) If you mix blue and yellow
you get green.
• The order of these two clauses can be inverted: We’ll go for a swim in the lake
if it doesn’t rain tomorrow.
ZERO CONDITIONAL • If clauses type 0 are used when we describe a result occurring every time a particular condition takes place. With these general facts, we use the following verb tenses: IF + Present simple (if clause)
Present simple (main clause)
If I’m late If there’s a fire
I usually go to work by car. you must call the police immediately.
FIRST CONDITIONAL • If clauses type 1 refer to a condition that will lead to a future result or consequence: IF + Present simple (if clause)
will / won’t – Base Form (main clause)
If we are late If you don’t train harder
we’ll have to call Mum. you won’t be able to win the race.
OTHER CONDITIONAL CONJUNCTIONS AND PHRASES • As long as underlines the condition as being mandatory (only if); more formal phrases with this meaning are provided / providing (that) and on condition (that): You can borrow my bike as long as you bring it back by tomorrow. (= only if you bring it back) • In case is used to suggest that we do something when a certain situation occurs: I’ll bring my umbrella in case it rains. (= if this happens) • Unless means if not, but you only use it when the result will be stopped by the condition. It is always followed by an affirmative verb form. Compare these examples: ➝ You won’t pass the test unless you study harder. OR: You won’t pass the test if you don’t study harder. (not studying will stop you from passing) ➝ I’ll be surprised if he doesn’t pass the test. (not: unless he passes) FUTURE TIME CLAUSES • Time clauses referring to the future take Present Simple just like first conditional clauses. The main time conjunctions are when – as soon as – until / till – before – after: Don’t worry, I’ll call you as soon as the plane lands. (= right after landing) Will you go to univerity after you finish school? (or: … after you’ve finished...) Note! • Of course the two clauses may be inverted. In fact, in questions they are ALWAYS inverted, so always look at the position of if, when, or other conditional conjunctions to choose the right tense: What will you do if you don’t find the keys anywhere? We’ll go for a walk unless it rains. • Remember that you may also use an Imperative in the main clause for situations in which you suggest doing something. Study these examples: If you need any further information, do not hesistate to contact me. Call me when you have time, please.
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