n.

1. 广度，宽度；长度[U]
   Standing on the top of the mountain, you can see the full extent of the forest.

   站在山顶上，你可以看到森林的全貌。

2. 程度；限度；范围[U][the S]
   To a certain extent, I am responsible for the delay.

   在一定程度上，我对拖延负有责任。

3. 一大片（地区）[S]

n.

1. the area covered by something.
   ▸the size or scale of something.
2. the degree to which something is the case:
   everyone has to compromise to some extent.