1.someone who learned to fight in the streets rather than being formally trained in the sport of boxing

2.an aggressive and violent young criminal

3.a cruel and brutal fellow

4.not given to gentleness or sentimentality;

a tough character

5.very difficult; severely testing stamina or resolution;

a rugged competitive examination

6.physically toughened;

the tough bottoms of his feet

7.substantially made or constructed;

sturdy steel shelves

8.violent and lawless;

the more ruffianly element

9.feeling physical discomfort or pain (`tough' is occasionally used colloquially for `bad');

my throat feels bad

10.tough to cut or chew

11.unfortunate or hard to bear;

had hard luck

1 . 強硬

But Putin is less toughin dealing with Iran ., 但是普京在處理伊朗問題時并不那么強硬.

2 . 堅韌

Tough times never last , but toughpeople do . Tough people stick it out ., 時運不濟不會沒完沒了 , 堅韌的人總會堅持到底.

3 . 硬朗

Then her fair , toughface appeared on the screen ., 然后 , 她美麗硬朗的面孔出現在屏幕上.

4 . 堅硬的

touch vt. 觸摸，接觸tougha. 堅硬的；結實的；棘手的，難解的tour n. 參觀, 觀光, 旅行

1 . 和韌性

center segregation and its effect on microstructure and toughness of continuously cast steel plate ., 連鑄鋼板中心偏析及其對組織和韌性的影響.

1 . 刻痕韌性

notch shock test 切口振動試驗notch toughness 刻痕韌性notch wedge impact 楔擊缺口沖擊試驗

1 . 斷裂韌性

...chanism specimen)：可以控制裂縫擴展速率的樣品，用于測定斷裂韌性與應變能釋放速率 。斷裂韌性(fracture toughness)：材料在斷裂過程中吸收能量的能力。斷裂伸長率(elongation at break)：材料在斷裂點處的應變，習慣上用百分數表示。.

1 . 有力的敵人

it's a tough / not an easy proposition .這是個有力的敵人，他們不會等著你站在船上去攻擊他們就已經早早的將你徹底粉碎了。

1.Don't be such a tough baby. Who do you think you are?

別這樣無法無天, 你以為你是誰啊？

2.I wish Jill wasn't such a tough nut to crack.

我希望吉爾不是個那么難打交道的人。

3.This problem is a tough egg to crack.

這一問題可真令人難以理解。

4.Getting them all here on time will be a tough nul to crack.

要他們全都準時到將是件很難辦到的事。