flat harder

例句：

1. 1. The floor is very flat and easy to clean.
   地板非常平坦，容易清洁。
2. 2. The car was parked on a flat surface.
   汽车停在一个平坦的表面。
3. 3. She moved her desk to the flattest part of the room.
   她把桌子搬到房间最平坦的地方。