Conditional sentences: zero, first, second and third

conditional sentences

1. zero conditional

   • certainty
     • something which is generally true
       • now
   • if + present tense/present tense

2. first conditional

   • probability
     • something which is possible and will probably happen
       • future
   • if + present tense/will + infinitive

3. second conditional

   • possibility
     • something which is possible and will probably not happen
       • future
   • if + past tense/would + infinitive

4. third conditional

   • impossibility
     • something which did not happen and is not possible to be changed
       • past
   • if + past perfect/would have + past participle

5. structure

   • if + condition/result
   • result/if + condition