🧩 词语组成解析
black
[blæk]
adj. 黑（色）的;黑色人种的;黑暗的;不加牛奶的;
n. 黑色;黑人;黑颜料;黑暗;
v. 使变黑;抵制;拒绝;使变黑暗;
tree
[tri]
n. 树;木料;树状图;宗谱;
vt. 把…赶上树;使处于困境;把鞋型插入（鞋内）;
fern
[fə:n]
n. <植>羊齿植物，蕨类植物;
🗣️ 情景例句
Public transportation is quite convenient in this city.
在这个城市里，公共交通很方便。
Measure thrice before you cut once.
三思而后行。
When he died, however, his brothers found it impossible to keep the secret any longer.
他死后，他的弟弟们才觉得无法再保守这个秘密了。