6. I am bad at English, so I can't do homework.

=> I could do homework, if I were not bad at English.

7. He doesn't practise speaking French, so he doesn't speak it fluently.

=> If he practised speaking French, he would speak it fluently.

8. The meeting can be cancelled because it snows heavily.

=> If it didn't snow heavily, the meeting could not be cancelled.

9. We don't go because it will rain.

=> If it doesn't rain, we will go.

10. John is fat because he eats so many chips.

=> If John didn't eat so many chips, he would not be fat.

GOOD LUCK!!!

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