Here are the filled-in blanks based on the provided context:

1. I have no energy and can't do any work. I **feel** **weak**.
2. I feel very hot and sick. I think I have a **fever**.
3. The doctor told me to **eat** after eating, three times a day.
4. If you eat a healthy diet, you don't need to **take** **supplements**.
5. You should wear a thick jacket and scarf to **keep** **warm** in.
6. I have a cough and a **sore** **throat**. It hurts when I drink.
7. Many teens **prefer** to do homework or watch TV. That's bad for their health because they won't get enough sleep.
8. You look tired. You should **rest**.