main materials

• 主要材料

main materials的用法和样例：

例句

1. Tomatoes and cheese are the main ingredients of pizza.
   番茄和起司是披萨的主要材料。
2. Also, the nozzles fitting in three roller bits for oilwell drilling have been developed with hard alloy materials.
   用硬质合金为主要材料研制出了石油钻井用自振空化射流喷嘴。