We have lived in the same house for twenty years.
我们在同一座房子里住了二十年了。
I was twenty years old and ready for anything.
我当时二十岁，什么都愿意去做。
Twenty guests are enough, I would have thought.
我觉得二十位客人就够了。
There were twenty or so people there.
那儿有差不多二十个人。
Pick a number from one to twenty.
从一至二十中挑选一个数。