Надо заменить one/one's This bag is very old. I need a new bag Small pineapples are...

Question

Надо заменить one/one's
This bag is very old. I need a new bag
Small pineapples are sweeter than big pineapples.
The new smartphones are much faster than the old smartphones

Answer 1

This bag is very old. I need a new one.
Small pineapples are sweeter than big ones.
The new smartphones are much faster than the old ones.