Question

1. I sleep for 7 or more hours a day.
2. I sleep for more than 7 hours.
3. I sleep for over 7 hours.
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What is the difference among them?

Answer 1

First, a number (7) should be spelled out (seven) if it's twelve or under.

1 means you sleep for seven hours (maybe more, sometimes).

2 & 3 mean you always sleep for more than seven hours.