首先，相对于海滩松在西海岸的连续分布，短叶松仅呈零散的块状分布。

The first is that jack pines occur in patchier stands than the continuous swaths of lodgepole on the west coast.

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一些科学家认为，这种林业害虫，不可避免地会借由加拿大北部针叶林带中的短叶松走廊，迅速向东扩散。

Some scientists say it is inevitable that the tree-killing insect will spread all the way east via a corridor of jack pines across northern Canada's boreal forest.

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一种美国水生植物，叶肾形或圆心形，佛焰苞具有短的柄或无柄；通常扎根在池塘和水沟的底部淤泥中。

American plant with roundish heart-shaped or kidney-shaped leaves; usually rooted in muddy bottoms of ponds and ditches.

youdao

You don't have to do this for Wednesday but let's say for next Monday, and that is: I'd like you to memorize a short poem by Yeats or by Frost, either one.

你们不用今天做,下星期一吧：,我想让你们背一首短诗,叶芝或者弗罗斯特的都行。

耶鲁公开课 - 现代诗歌课程节选