1. 回收利用；循环利用
    If you recycle things that have already been used, such as bottles or sheets of paper, you process them so that they can be used again.

recycle的解释

    e.g. The objective would be to recycle 98 per cent of domestic waste...
           目标是对 98%的生活垃圾进行回收利用。
    e.g. All glass bottles which can't be refilled can be recycled...
           所有不能再次装用的玻璃瓶子都可以被回收利用。