Mustn't or don't have to

Explaination:

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Exercises:

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Put into order:

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Complete the sentences:

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Conditional Sentences

FIRST CONDITIONAL :
If + present tense with will 

-- talk about probable or possible present or future situations
* If I leave at 5.30, I will be there at 6.15.

SECOND CONTITIONAL:
If + past tense with would
-- talk about unreal situations or improbable present or future situations
* If I were the manager, I would introduce a coffee break

THIRD CONDITIONAL:
If + past perfect tense with would have + past participle
-- to talk about unreal situations in the past and their result
* If I had seen you, I would have said hello but I didn't see you. 

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Exercise:
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