Calcium is a soft white element which is found in bones and teeth, and also in limestone, chalk, and marble.
英汉词典释义
n.
〈化〉钙
We need calcium to make bones.我们需要钙来壮骨。
英英词典释义
Noun
1. a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals