New data fromUnited States Forest Service ecologists show that for every dollar spent oncontrolled smallscale burning, forest thinning, and the trainning of firemanagementpersonnel saves seven dollars? on havingto extinguish.

這句錯(cuò)在哪兒，麻煩老師解答

第一要明確：1. spend+錢+on+sth? 2. spend+錢+on+doing sth.如：1. She spent 1,000 yuan on a new dress. 2. I have spent 100 yuan on updating my computer systems.所以，原句中的controlled要改為controlling ;另外去掉for；注意saves的主語是every dollar，這兩者之間從spent到personnel為后置定語.整個(gè)句子是強(qiáng)調(diào)預(yù)防失火的重要程度，防患于未然.