用 up from across through填空

问题描述:

用 up from across through填空
1.Would you please have a walk with me ____ the beach?
2.The climbing team went ___ the forests.
3.Can you come down ____the lift?I have something to ask you.
4.There is a Great Green Wall____ northern part of China.

1.up
2.through
3.from
4.across