1. He needs to cut back on junk food and do more exercise.

2. I wouldn't have time to scout the area for junk.

3. They are certainly not junk, and for some people, they may be the best computers money can buy.

4. Too many children were eating junk food, especially chips.

5. I don't know about yours, but mine are all about junk food.

6. When we were children, we barely had any junk food available and we turned out just fine.

7. I guess my only issue with the internet is that people are constantly eating junk food all the time.

8. Don't eat too much junk food, it's bad for your health.

9. Many students like eating junk food.

这些例句涵盖了"junk"作为名词（垃圾、废物）和动词（搜寻）的不同用法，以及它在日常对话中的应用。希望这些例句能帮助你更好地理解和运用这个词。