说到笑容，首先要解释一下，smile 是指没有笑出声音的笑容，而 laugh 则是有发出声音的笑。基本款搞清楚之后，来学点进阶版的：

knowing smile 会心一笑

My friend nodded and gave me a knowing smile.

我朋友对我点点头，露出会心的一笑。

The two boys smiled at each other knowingly. 
那两个男孩很有默契的相视而笑。

snicker 偷笑

The students snickered behind the teacher’s back.

同学们在老师背后偷笑。

furtive smile 偷笑

The shy little girl gave him a furtive smile.

那个害羞的小女孩对他偷笑。

laugh out loud 哈哈大笑

I laughed out loud when I saw that funny video.

我看那个搞笑影片的时候笑翻了。

laugh heartily 哈哈大笑

The audience laughed heartily at the comedian’s joke.

观众被那名喜剧演员的笑话逗得哈哈大笑。

wry smile 苦笑

When I asked about Roger’s divorce, he just gave me a wry smile. 
当我问及罗杰离婚的事，他只给我一个苦笑。

He just smiled wryly when I asked about his divorce. 
我问他有关离婚的事，他只对我苦笑。

laugh bitterly 苦笑

The man laughed bitterly as he talked about his troubled past. 
说到自己不堪回首的往事,那男子苦笑了ㄧ声。

smirk 假笑，得意地笑

What are you smirking about?你笑得那么贼是为什么？

Wipe that smirk off your face! 
卸下你那虚假的笑容！

sneer 冷笑，轻蔑地笑

Brad always sneers at the way I dress.布莱德总是对我的穿著嗤之以鼻。

She looked at him with a sneer of disgust. 
她一脸厌恶的看著他冷笑。

giggle 傻笑，咯咯笑

Jane always giggles when she gets nervous.小珍紧张时都会傻笑。

Monica’s annoying giggle is driving me crazy. 
莫妮卡恼人的咯咯笑声快把我逼疯了。

chuckle 轻笑，暗自发笑

Bill chuckled as he read the story.比尔在读那个故事的时候暗自发笑。

That comic strip is always good for a chuckle. 
那则连环漫画总是令人发噱。