descend
I watched the city get smaller as the plane soared into the sky.
It's cold this far up the mountain, so let's climb down a bit.
practicable
That bike costs at least a year's worth of babysitting money.
She has supplies and he has tools, so together they can build a treehouse.
undertaking
I don't mind reviewing your work, as checking numbers goes pretty quickly for me.
I put off cleaning my room for so long that it was a huge chore.
expedition
The explorers gathered the supplies they would need for the journey to study the new land.
The scientists were pleased with the result of their experiment.
civilized
The archaeologist found proof that ancient peoples had complex systems of transportation and government.
After a year in the city, it was a relief to spend a day hiking in the quiet countryside.
BONUS
