雅思阅读预测：阅读考试里的长难句解析

1. Indeed, the purple colour extracted from a snail was once so costly that in society at the time only the rich could afford it.

语法现象：后置定语

理解：的确，从蜗牛身上提取出来的紫色染料曾经非常贵，因为在当时的社会条件下，只有那些富人才能*得起。

2. He was attempting to manufacture quinine from aniline, an expensive and readily available coal tar waste product.

语法现象：同位语

理解：他图从苯胺中产出奎宁，其原料(苯胺)是廉价而充足的煤焦油。

3. Built from stone and supported by pillars, they also included pavilions that sheltered visitors from the relentless heat.

语法现象：定语从句

理解：它们由石头建成，由柱子支撑，还有一些供来访者躲避酷热的凉亭。

4. As their name suggests, stepwells comprise a series of stone steps descending from ground level to the water source as it recedes following the rains.

语法现象：后置定语

理解：正如其名称所示，阶梯井由一系列是由石阶构成的，这些石阶从地平面想下延伸至水源，水位往往会随着雨水变化。