NOT THICK 薄; 细, if something is thin, there is only a small distance between its two opposite sides or surfaces

薄的; 细的;

a thin gold chain

一条细金链

She's only wearing a thin summer jacket (=a jacket made of light material) .

她只穿了一件薄薄的夏季短上衣。

two thin slices of bread

两片薄薄的面包

The road was covered with a thin layer of ice.

路面上覆盖着一层薄薄的冰。

The skin on the eyelids is the thinnest on the body.

眼睑的皮肤是人体最薄的皮肤。

Keep your voice down – the walls are paper thin.

小点儿声，这些墙很薄。

NOT FAT 不胖的, having little fat on your body

〔身体〕瘦的;

He was tall and thin, with short brown hair.

他又高又瘦，一头棕色的短发。

He has long thin hands.

他有一双瘦长的手。

Most high school girls say they want to be thinner.

大多数高中女生说她们希望能更瘦些。

HAIR 毛发, if someone has thin hair, they do not have a lot of hair

〔毛发〕稀疏的:

a thin straggly beard

稀疏杂乱的胡子

His hair is quite thin on top.

他头顶上的头发很稀疏。

LIQUID 液体, a liquid that is thin flows very easily because it has a lot of water in it

〔液体〕稀的，淡的;

thin paint

稀油漆

SMOKE / MIST 烟/雾霭, smoke or mist that is thin is easy to see through

〔烟或雾霭〕稀薄的，淡薄的;

The fog is quite thin in places.

有些地方雾很薄。

AIR 空气, air that is thin is more difficult to breathe than usual because it has less OXYGEN in it

〔空气〕稀薄的:

the thinner air high in the mountains

高山上较为稀薄的空气

EXCUSE / ARGUMENT / EVIDENCE ETC 借口/论据/证据等, a thin excuse, argument, or evidence is not good or detailed enough to be useful or effective

〔借口、论据或证据〕贫乏的，空泛的，不能令人信服的:

Evidence that capital punishment deters crime is pretty thin.

极刑能制止犯罪的论据不能令人信服。

a thin margin / majority etc, a very small number or amount of something

极小的差额/微弱的多数等:

Engle beat Blanchard by a razor-thin margin (=a very small number of votes) in the race for governor.

恩格尔在州长竞选中以极其微弱的多数票击败布兰查德。

SMILE 笑, a thin smile does not seem very happy or sincere

不真心实意的; 冷淡的:

Charlie gave her a thin smile.

查利向她牵强一笑。

VOICE / SOUND 话音/声音, a thin voice or sound is high and unpleasant to listen to

尖声细气的; 刺耳难听的:

His thin voice trailed off.

他尖细的声音渐渐小了下去。

the thin end of the wedge, [BrE spoken] an expression meaning something that you think is the beginning of a harmful development

糟糕事情的开始:

Workers believe the job cuts are just the thin end of the wedge.

工人们认为裁员只是厄运的开始。

be thin on the ground, if a particular type of person or thing is thin on the ground, there are very few available

不是随处可见的，是少有的:

Taxis seem to be thin on the ground.

出租车好像不多。

be having a thin time (of it), [BrE spoken] to be in a difficult situation, especially one in which you do not have enough money

过得不顺，遇到麻烦〔尤指钱不够用〕

be (walking / treading / skating) on thin ice, to be in a situation in which you are likely to upset someone or cause trouble

处境不妙，很可能招惹麻烦:

I was on thin ice, and I knew it.

我当时处境微妙，我知道的。

disappear / vanish into thin air, to disappear completely in a mysterious way

神秘地消失不见:

Victor and his kidnappers had vanished into thin air.

维克托和劫持他的人己经消失得无影无踪。

out of thin air, out of nowhere, as if by magic

凭空，无中生有:

It seems like researchers have just pulled the numbers out of thin air.

这些数据就好像是研究人员凭空变出来似的。

thinly. Many teachers think this is not correct English.

薄薄地; 细细地〔许多教师认为这种用法不正确〕:

Don't cut the bread so thin.

别把面包切得这么薄。

[I,T] also thin out to become fewer in number, especially when there were many before, or to remove people, plants, or things so that fewer remain

（使）〔拥挤的人群、植物、物品等〕变稀少; 散去:

The crowd had thinned out and only a few people were left.

人群渐渐散去，只剩下几个人了。

The trees thinned as we got closer to the top of the mountain.

随着我们慢慢爬上山顶，树木也变得越来越稀少。

Traffic was finally thinning.

路上行驶的车辆终于越来越少了。

Thin the carrots to two inches apart.

把胡萝卜间成相隔两英寸。

Her hair had been thinned and cut shorter.

她的头发削薄了，剪短了。

[I,T] to make something thinner or to become thinner

（使）变薄;（使）变稀;

The clouds had begun to thin.

云层渐稀。

A narrow smile thinned his lips.

一道浅浅的笑容使他的嘴唇看上去更薄了。

[T] also thin down to make a liquid weaker by adding water or another liquid

〔掺水等〕使稀薄，使变淡:

Thin the sauce by adding milk.

加入牛奶把调味汁调薄。

The pastels can be thinned with water.

这些水粉颜料可以用水稀释。

[I] if someone's hair is thinning, they have less hair than they used to

〔头发〕变稀疏，变稀少:

a tall man with thinning hair

头发日渐稀疏的高个男人

thin the ranks, if something thins the ranks of a group of people, there are fewer of them as a result of it

减少人员:

Illness had thinned our ranks.

疾病使我们人员减少了。