1. Do you sleep less than 5 hours a day?
2. I like you less than him.
3. I ate fish less than fruit.
4. I ordered fried chicken less than noodles.
5. I player soccer less than baseball.
6. I studied math less than English.
7. I helped Mother less than my brother.
8. I worked less than the person.
9. I ran less than Bill.
10. I slept less than Ted.
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Are the sentences containing 'less than' all grammatical? Would you correct sentences having errors? Thank you.
http://grammar.ccc.commnet.edu/grammar/noncount.htm
This page explains and lists both "count" and "non-count" nouns. You use "less than" with non-count nouns; you use "fewer than" with count nouns.
Also, with comparative forms, you need to make sure the comparison is complete. I've also corrected fuzzy comparisons below.
1. Do you sleep fewer than 5 hours a day?
2. I like you less than he does.
3. I ate fish less often than fruit.
4. I ordered fried chicken less often than noodles.
5. I played soccer less often than baseball.
6. I studied math less than English.
7. I helped Mother less than my brother did.
8. I worked less than the other person did.
9. I ran less than Bill did.
10. I slept less than Ted did.
Let me know if you have questions.