White pins are often covered with tin, and black ones with black paint.

白色的大头针一般是镀锡的，黑色的大头针则涂上了黑漆。

ICC does buy US made steel but says imports bridge a gap in supply for high-grade tinplated steel needed for blemish-free lithographic printing.

独立金属罐头公司确实购买了美产生的钢铁，但同时也表示，进可以弥补高档镀锡钢的供应缺，而高档镀锡钢正是无瑕疵平版印刷所需要的原材料。

Untinned copper can be dangerous and acidic foods cooked in it can turn green and make you ill or even die.

未镀锡的铜具很危险，用它煮的酸性食物会，你生病甚至死亡。

An important part of the girls cleaning the copper is to make sure that the inside is still tinned.

女仆们清洁这些铜具的一个重要原因是确保铜具内部的镀锡不掉。

But not all of the copper is tinned, this one here is untinned because it's a sugar pan.

但并不是所有的铜具都是镀锡的，这里的这一个没有镀锡，因为它是一个糖锅。