material time

例句：

1. 1. The engineer used a material called steel to build the bridge.
   工程师使用一种叫做钢的材料来建造这座桥。
2. 2.The scientist collected materials for his experiment.
   科学家收集了实验所需的材料。
3. 3. The book is filled with interesting materials for children to learn from.
   这本书充满了有趣的材料，供孩子们学习。