词汇点睛
cut down减少;削减
[观察]Well, to cut down air pollution, we should take the bus orsubway instead of driving.
哦，为了减少空气污染,我们应该乘坐公共汽车或地铁,而不是开车。

探究 cut down意为“减少;削减”，此时通常和pollution, cost,amount等词搭配。
拓展 cut down还有“砍伐;砍倒”之意，此时通常和tree搭配。The officers have told us not to cut down the trees.
那些官员告诉我们不要砍伐这些树。