Are these usages of ‘outside’ and ‘out of’ grammatical?
Students should behave properly
a) inside and outside school
b) inside and outside of school
c) in and out of school
Those are all OK, but my preference is for (a).
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nicetomeetyoua) inside and outside school
This is the simplest choice.
nicetomeetyououtsideof
This is possible but wordy. The second word is superfluous.