Beijing is one of the (polluted) cities in the world.

Hippopotamus is one of the (dangerous) animals in the world.

Vienna is (far) from Prague than Budapest.

This shop is really expensive. The (cheap) shirt costs $100.

This exercise is (difficult) the previous one. It took me half an hour.

I never want to go to that restaurant again. I had (bad) dinner of my life.

That was (boring) film I have ever seen. I fell asleep.

This is the (busy) street in this town. Everyone comes shopping here.