1.scratch的基本意思是“搔”“抓”,多指用带光(而非带刃)的东西如手指甲等去抓搔,也可表示在平面上刮线或穿孔。动作的发出者多没有明确的目的,而动作的承受者多受到一定程度的损害。引申可表示“刮伤”“勾掉”“刻画”“艰难地谋生”“退出比赛”等。
2.scratch既可用作及物动词,也可用作不及物动词。用作及物动词时,接名词、代词作宾语。

scratch about(v.+adv.)
扒,刨 strip off or dig in light movements
▲scratch about
The farmyard was quiet, with just a few chickens scratching about.这农家庭院静悄悄的,只有几只鸡在四处扒食。

scratch away(v.+adv.)
抓; 刮 strip off or dig
▲scratch away
If you keep scratching away at that spot, you'll break the skin.你要是不停地抓那个小包会抓破皮的。
▲scratch sth⇔away
◇ 用于be ～ed 结构
Most of the paint has been scratched away by heavy wear.由于磨损严重,大部分油漆已剥落。

scratch from(v.+prep.)
从…中除名 remove sb's name from sth
▲scratch sb from sth
We had to scratch two players from the team because of damaged knee joints.有两名选手膝关节受伤,我们只好不让他们参加比赛了。
◇ 用于be ～ed 结构
Jim should have an easy victory, as two of the best runners have been scratched from the race.吉姆应该很容易地轻易取胜,因为两名优秀赛跑运动员已经从比赛中除名了。

scratch out(v.+adv.)
▲scratch sth⇔out
1.刮掉; 划去 remove off; cancel or erase by drawing a line through
Scratch my name out please.请把我的名字划掉。
◇ 用于be ～ed 结构
Names had been cut on the wall, but had then been scratched out.墙上曾刻着名字,但后来被刮掉了。
2.勉强维持 make or get with difficulty
It wasn't easy scratching out a living in those hard times.在那段艰难的日子里,糊口真不容易。

scratch up(v.+adv.)
▲scratch sth⇔up
1.刮坏,磨坏 spoil sth by making marks with sth sharp
The porters scratched up the desk.搬运工们把桌子刮坏了。
◇ 用于be ～ed 结构
The surface of the table has been all scratched up by years of heavy use.由于长期严重磨损,桌子表面已粗糙不堪。
2.掘起,挖出 dig sth out
That cat has scratched up all my young plants again!那只猫又把我种的那些幼苗给扒出来了!

用作不及物动词
▲S+～(+A)
The dog is always scratching.那条狗老是搔痒。
The pen scratches badly.这支钢笔钩纸钩得利害。
用作及物动词
▲S+～+n./pron.
He has a curious habit of scratching his ear while he speaks.他有一种奇怪的习惯,一讲话就搔耳朵。
Please leave off scratching your head.请不要搔头了。
Scratch yourself if you itch.如果你觉得痒,搔好了。
The cat scratched my hand.猫把我的手给搔了。
The cat has scratched a hole in the flowerbed.猫在花坛上扒了一个坑。
The brambles scratched my legs.荆棘刺伤了我的双腿。
The knife has scratched the table.小刀划坏了桌子。
I hope you are not going to scratch me.我希望你不会把我的名字从比赛中划去。
◇ 用于be ～ed结构
The horse was scratched.那匹马退出比赛了。

scratch, grind, scrape
参见scrape条。

from scratch
〈非正〉从头做起,从零开始starting from the beginning or with nothing
It's completely ruined, so we'll have to start from scratch.它完全毁了,我们只好从头做起。

up to scratch
〈非正〉情况良好,达到标准in(to) good condition or at〔to〕 an acceptable standard
Her performance wasn't up to scratch.她的演奏没达到水准。

His dog just gives a scratch at the door when it wants to come in.他的狗想进来时就用爪子抓门。
Her face was covered with scratches.她脸上有很多划痕。
I heard the scratches on the old records.我听到旧唱片的沙沙声。