The material typically used for the pages was parchment, which is animal skin that's stretched and dried under tension, so it become s really flat and can be written on.

书页通常使用的材料是羊皮纸，羊皮纸是一种动物的皮肤，其在张力的作用下被拉伸和变干，因此它会变得非常平整，并且你可以在上面写字。

youdao

Can we have a calm heart, wanted to sing the song as: pale is really flat. This is the life.

可我们要有一颗平静的心，就想歌中唱的那样：平平淡淡才是真。这才是生活。

youdao

The road was really flat. However, the judges' eyes hidden in the dark were fixing closely on every girl from the countries around the world.

公园的道路是那么平坦，但躲在暗处的裁判们的一双双眼睛却在紧盯着参加竞走的来自世界各个国家的每一位姑娘。

youdao

They just look that way, but really are many flat pieces put together side by side.

VOA: special.2009.12.29

"You look for a banjo, then you look for a flat top guitar, got to have the stand-up bass, a fiddle works really well, and then you get the old mandolin in because a mandolin really has got some good sound to it too."

VOA: standard.2010.05.28

Sharapova, champion at Indian Wells in 2006 but playing her first tournament in five weeks after suffering a viral infection, was frustrated after a "really flat" performance.

BBC: Caroline Wozniacki

There is a scramble over rocks to reach the top, which really is flat, but the easy walking is around the base.

BBC: Accessible wilderness in Alaska��s largest city

The match is at Centurion and the wicket looks like a really good flat one so hopefully it will be a high-scoring game.

BBC: Filling the void