1. I would prefer not to eat that.
2. He slaved at his job so his family would have everything they needed.
3. Your cholesterol balance is good.
4. He slipped into the room.
5. Clip two sheets of paper together.
6. The whole universe knows it.
7. I won't force you to come, but you'll miss out!
8. These children come from upper-class families.
9. I fell off my bike and scraped my elbow.
10. He has passed first on the list.
11. Letters are the element out of which all our words are formed.
12. Don't upset the boat, or we may end up in the water.
(Would you check the sentences and correct errors, please? Have a great weekend.)