难句突破：

(1)   This is good news for the mine's 1,000 or so employees and for the town, which has depended on the diamond business since Sir Thomas Cullinan discovered a prospect there in 1898 that contained kimberlite, a rock that can be rich in diamonds.

[主体句式] This is good news for ...

[结构分析] 这是一个简单句，for后面的宾语比较复杂，which 引导的非限定性定语从句修饰the town，在该从句中有一个since引导的状语从句；在该状语从句中，that 引导的定语从句修饰prospect, a rock...是kimberlite的同位语。

[句子译文] 这对于这个矿的1000名左右的雇工以及这个小镇来说是个好消息，这个小镇从1898年Thomas Cullinan爵士发现该矿含有金伯利岩（可能富含钻石的一种岩石）后，就一直依赖钻石生意存活。

(2) It started focusing on higher returns rather than market share, and has been revamping its mine portfolio, selling off mines that are no longer profitable and investing in more enticing operations, such as its mine off the west coast of South Africa, its Voorspoed operation in the Free State province, and two new mines in Canada.

[主体句式]It started focusing on..., and has been...

[结构分析] 这是一个并列句，由连词and 连接，后半分句结构比较复杂；has been 后面带有三个并列的成分，第二个成分selling off mines后面有that 引导的定语从句，第三个成分中such as 后面都是用来修饰operations的。

[句子译文] 它开始修关心更高的回报率而不是市场份额了，也一直在修改它的矿产组合，卖掉不再盈利的矿产，投资更让人动心的项目，如南非西海岸的矿产、自由州省的Voorspoed项目、加拿大的两处新矿。