That statement comes not, as you might imagine, from a stereotypical tree-hugging, save-the-world greenie 环保主义者, but from Gordon Brown, a politician with a reputation for rigour, thoroughness and above all, caution.
2016年6月六级真题（第三套）阅读 Section B
柯林斯高阶英汉双解学习词典释义
ADJ-GRADED
(行为、活动)详细的，全面的，彻底的
A thorough action or activity is one that is done very carefully and in a detailed way so that nothing is forgotten.