In the summer , chalco took over baotou aluminium .

今年夏天，中铝收购了包头铝业。

And working with aluminium can be more expensive .

并且，铝零件的制造更加昂贵。

Why use copper when you can use aluminium ?

能用铝，为何要用铜呢？

Aluminium requires lots of expensive electricity to produce .

生产铝需要耗用很多昂贵的电能。

Aluminium cans are brought ready and painted .

铝罐在购买时就是成品，而且已经喷好图案。