Here are the combined sentences for each set:

1. **It was raining heavily, but the boys went out to play football.**

2. **He doesn’t often update his Facebook; however, he sometimes uses Messengers to chat with his classmates.**

3. **Stress can have physical effects on teenagers, and it also affects their social life.**

4. **Ann has to lose weight, so she has to eat a balanced diet.**

5. **Jim joins the football club because he wants to make friends with other members.**

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