1. It's bad to bury plastic because it doesn't decompose
2. He was unhappy about the problem, so he wrote a letter to the council.
3. I've got a shopping bag, so I don't need to use plastic bags.
4. We're worried about plastic bags because they're bad for the environment .
5. I feel cheerful today because it's my birthday.
6. They were very hungry, so they ate a packet of biscuits
