leaf n.叶子
观察 It has a red leaf on it!它上面有一片红色的树叶![探究] leaf为名词，意为“叶子”，其复数形式为leaves。以f或fe结尾的名词，变复数时，要把f或fe变为V，再加es。例如:half—halves knife—knives

口诀 巧记f, fe结尾的名词变复数记忆口诀
妻子(wife)拿刀(knife)去宰狼(wolf),小偷(thief)吓得发了慌。
架子(shelf)下面把命(Ilife)藏，半(half)片树叶(eaf)遮目光。

活学活用
(1)在春天，树上的叶子变成绿色。Theleaveson trees turn green in spring.
(2)请把西瓜切成两半。Please cut the watermelon into two halves