klettern 用英语:

How long does it take to clamber up Mount Everest?

You can't jump out the aeroplane and then clamber back through the cockpit hatch,

They clambered over/up the rocks.

The goat was able to clamber all over the rocky mountainside.

How long does it take to climb Mount Everest?

we began to climb the hill / the air became colder as they climbed higher / we decided to climb to 6,000 feet

to climb walls