The empty tree serves as a warning that we cannot pretend to be spiritually alive, for we won't bear any fruit.

这棵毫无果子的树是一个警惕，它要提醒我们，活泼的属灵生命是不可以佯装的，因为我们不可以把果子逼出来。

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The sum of an empty tree is zero, and the sum of other trees is the sum of the left tree plus the value of the Integer plus the sum of the right tree.

空树的汇总是零，其他树的汇总是左树加上Integer的值再加上右树的值。

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After the class, small squirrel found a empty tree, he put some leaves and dry grass in it. Squirrel finished his home work, after that he went to monkey's home happily.

放学后，小松鼠找到了一棵空心的树，里面铺了树叶和干草，小松鼠盖完了房子完成了作业，高高兴兴地去找小猴子。

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The painting shows melting clocks,insects, and a dead tree in an empty landscape.

VOA: special.2010.03.24

Like the proverbial tree falling in an empty forest?

WSJ: The Times They Are A-Changing

In other photos, a wreath in the shape of a Christmas tree dangles above highway construction, and a "Happy Holidays" banner casts its shadow on a highway empty except for a single truck.

WSJ: rom Lee Friedlander at Janet Borden Gallery