1 . Tianjin Tower is ________ than many other buildings in Tianjin.

A．tall

B．taller

C．the tallest

D．the taller

2 . What a large tree it is! It is as ________ as a five-floor building.

A．tall

B．taller

C．small

D．smaller

3 . —How ________ is the Grand Canyon?
—If you put the two tallest buildings in the world on top of each other at the bottom of the canyon, they still would not reach the top.

A．long

B．deep

C．wide

D．tall