这个句子结构比较复杂。我理解是这样的：The thrilling clamour grew louder 动词1, grew nearer 动词2, muffled 动词3 now and then 短语1 for a few moments 短语2 （ as the trail （which the dogs were following 从句2） led through some dense thicket of spruce or fir 从句1）. 这样翻译供你参考：令人颤抖的喧嚣声越来越大，越来越近，而当狗所追踪的痕迹时而穿过茂密的云杉或冷杉树丛时，这喧嚣声就沉闷片刻。（可能是狗钻过树丛时不太叫了，或者叫声被树丛掩盖了，也可能是狗在这里失去了方向而迟疑？）

妈逼鸡巴~~

Thank you very much. But it is a paragrah of a literature. The whole sentence is"The thrlling clamour grew louder, grow nearer, muffled now and then for a few moments as the trail which the dogs were following led through some dens thicket of spruce or fir". It is noise of the dog and they want to hunt a fix. How to translate? Could you help me?

thrilling means exciting, clamor/clamour means a loud noise. but the sentence has some incorrect grammar, should be something like: "The thrilling clamor grew louder, grew nearer, but is muffled now"