1、This explains the rules under which the library operates.这份材料说明了图书馆的运行规则。
2、The government brought in a controversial law under which it could take any land it wanted.政府推行了一项颇具争议的法令，根据该法令政府可以征用其所需要的任何土地。
3、She was filled with indignation at the conditions under which miners were forced to work.矿工们被迫在如此恶劣的条件下工作，她感到异常愤怒。
例句：
He signed an agreement under which he would be entitled to a commission on sales. 他签订了一项协议，这可使他获得销售佣金
例句：
The earth is， however， very different from the moon， which the American astronauts have found to be without life or vegetation， whereas our earth is very much alive in every respect.
实际上地球与月球有很大的不同。美国宇航员发现，地球上没有生命，没有植物生长，而地球在各个方面都生机勃勃。
语法：which引导非限定性定语从句，修饰the moon
只能用which，不用that的情况：1）先行词为that，those时，用which，而不用’s that which is under the desk在桌子底下的那些东西是什么2）关系代词前有介词时，一般用which，而不用 is the room in which he lives. 这是他居住的房间。3）引导非限制性定语从句，用which，而不用 came back，which made us happy. 汤姆回来了，这使我们很高兴。
