They improve the soil when their leaves fall.

落到地上的树叶还能改良土壤。

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Jump into the middle of the pile and throw the leaves up in the air so they fall down like snowflakes.

跳进堆中，向空中抛扔树叶，树叶就像雪花一样飘洒下来。

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For the first row nearest the fans, they generally suggested trees that lose their leaves in the fall or trees with waxy leaf surfaces.

距离风扇最近的第一排树木，他们一般建议种植秋季落叶的树木或者带有蜡质叶表面的树。

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For the first row nearest the fans, they generally suggested trees that lose their leaves in the fall or trees with waxy leaf surfaces.

VOA: special.2009.09.08

The leaves are about to fall but they haven't yet fallen.

这些叶子似坠非坠。

耶鲁公开课 - 弥尔顿课程节选

They make extra money helping their dad rake leaves in the fall and plan to start selling the toys they outgrow through a local twins club.

WSJ: How I Spent My Allowance: Twins Buy Toys, but Help Cats, Too

When they do, his googly eyes shake and leaves fall from the tree.

FORBES: X Is For Entertainment

When they do, his googly eyes shake wildly and leaves fall from the tree.

FORBES: Magazine Article