他收藏了很多不同年代的铜钱和银币。

Tā shōucáng le hěn duō bùtóng niándài de tóngqián hé yínbì.

He has collected many copper coins and silver coins from different eras.

这种电线里面是铜芯，导电性能比较好。

Zhè zhǒng diànxiàn lǐmian shì tóngxīn, dǎodiàn xìngnéng bǐjiào hǎo.

The inside of this type of wire is copper core, so it conducts electricity well.

古代人常用青铜制作武器和礼器。

Gǔdài rén chángyòng qīngtóng zhìzuò wǔqì hé lǐqì.

People in ancient times often used bronze to make weapons and ritual vessels.