Questions & Answers about Ten nowy plan jest jeszcze lepszy niż tamten.
They are demonstratives:
- ten = this
- tamten = that
In this sentence:
- ten nowy plan = this new plan
- tamten = that one / that plan
Polish often uses tamten by itself when the noun is understood from context. So tamten here really means tamten plan, but plan is omitted because it would be repetitive.
Because Polish allows you to leave out the noun when it is obvious.
So instead of saying:
- Ten nowy plan jest jeszcze lepszy niż tamten plan.
you can naturally say:
- Ten nowy plan jest jeszcze lepszy niż tamten.
This works much like English this one and that one, except Polish often does not need a separate word for one.