1.
V-I
When a part of your body itches, you have an unpleasant feeling on your skin that makes you want to scratch. 发痒
例：
When someone has hay fever, the eyes and nose will stream and itch.
当一个人染上花粉热时，会流眼泪、流鼻涕，还会感到眼睛和鼻子发痒。
2.
N-COUNT
Itch is also a noun. 痒
例：
Scratch my back – I've got an itch.
给我挠挠背–我痒痒。
3.
itching
N-UNCOUNT
痒
例：
It may be that the itching is caused by contact with irritant material.
那儿的痒也许是由于接触刺激物而引起的。
4.
V-T/V-I
If you are itching to do something, you are very eager or impatient to do it. 渴望; 渴望
[非正式]
[usu cont]
例：
I was itching to get involved.
我渴望参与。
5.
N-SING
Itch is also a noun. 渴望
例：
...cable TV viewers with an insatiable itch to switch from channel to channel.
…难以满足的、渴望不停变换频道的有线电视观众。
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