Here are the matches for the beginnings of the sentences with the correct endings:
If the temperature is below zero, e) water freezes.
If I don't get enough sleep, a) I'm really tired all day.
If you eat a lot of junk food, d) you gain weight.
If it doesn't rain, b) the flowers don't grow.
If the weather is sunny, c) we eat lunch outside.
If we are late for class, i) The teacher gets angry.
If people don't eat, i) they get hungry.
If I get up late, j) I miss my bus.
If you don't study for exams, h) you fail. They are difficult.
If you don't like your job, g) Look for another job!
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