solid axle

例句：

1. 1. The car is solidly built.
   这辆车结构坚固。
2. 2. The building is solid, but it's not very tall.
   这座建筑很坚固，但并不很高。
3. 3. The material is solid, but it's easy to cut with a knife.
   这种材料很坚固，但是很容易用刀切。