trees前面加什麼冠詞爲什麼

前面加冠詞the，例如：

1、They walked through the trees to a second hut， cunningly camouflaged against air surveillance.他們穿過樹林來到第二個棚子這個棚子經過巧妙僞裝，空中偵察不到。

2、We ran through the trees to Sabden noise of the river was beautiful in my went along the river to the village of Sabden ， and then it began to rain.我們穿過樹林來到了薩卜登小溪。潺潺的流水聲在我聽來十分悅耳。我們沿着河走到了薩卜登村，這時天下起雨來。