1. He sat in a tree.
  2. The cat is on the tree.
    Are the prepositions used in these sentences OK?
    Can I interchange the prepositions ‘on’ and ‘in’ in these sentences?
    Please comment.

Hi Allifathima,

There are many uses of ‘in’ and ‘on’ and it would be difficult to generalise but ‘in’ usually suggests ‘inside’ and ‘on’ indicates ‘on top of’. Sentence (2) isn’t clear because it would suggest the cat is on top of the tree. That would suggest a very big cat or a very small tree!