Student or Learner
There are a lot of students in our school.
Is it correct?
Can I use lots of/plenty of? I should I use lots of/plenty of only with uncountable words?
And what about the preposition, normally we use at school but when there's our...?
a lot of students is fine, though the phrase a lot is over used, more appropriate for speech than writing. Many works as well.
plenty of students suggests there is room for no more.
in our school means enrolled. They don't have to be sitting there at the moment.
at our school means they are there, now. Maybe a sports event that has invited several other schools to attend. There are a lot of students at our school today!