Too… Not too (this one is hard because it mean “also” or “in the extreme” which don’t really have opposites)

Their — Our

Aisle —Window (as in the aisle seat in a plane)

Heir — Forgotten (an Heir is one who has inherited so one who has not inherited would be… “Disowned” maybe.)

I’ll—You’ll

Pear—You can’t make an opposite to a fruit so maybe banana?

Hour—Hour ago? Its a unit of time, there’s no opposite really, this is hard because these words don’t really have opposites I’m just giving you the closest thing I can think of.

2) Their is a personal adjective, no opposite

3) Aisle is a noun. It really doesn’t have an opposite, but on an airplane a window seat is the alternative to an aisle seat.

4) heir is a noun. Again, it doesn’t really have an opposite. “Disinherited” is a stretch.

5) I’ll is a contraction for I will. Shan’t is “shall not”; take it if you want

6) Pear is a fuit — no opposite

7) Hour as a measure of time also has no opposite.