1. Math is complex, but it's necessary.

Question

2. Social studies looks simple, but it's informative.
3. Chinese characters is not simple but complex.
4. Technical arts is useful and important.
5. Home economics is both necessary and useful.
6. Fine arts is neither useful nor necessary.
7. Art is not only useful but also necessary.
8. Music looks simple, but it's important and necessary.
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I worte down 8 sentences related to subjects. Would you check unnatural sentences?

Answer 1

In 3, 'Chinese characters are ... '

All the others seem fine.