Well, you may refer to your friend casually as a 'mate' or a 'buddy,' and also you can use his job title when talking about his position in the restaurant:
"My mate up and left his waiter's job today."
To walk out = depart or leave suddenly or angrily.
leave suddenly, make a sudden departure, get up and go, storm off/out, flounce out, push off, depart, leave, get out, absent oneself, take wing; informaltake off
"He had walked out in a temper"
To up and leave = to move on a course : proceed — compare stop. : to move out of or away from a place expressed or implied : leave, depart. : to take a certain course or follow a certain procedure.
友達のことをカジュアルに
'mate' 又は a 'buddy,'と
表現することができ、
レストランでの彼の肩書
について話す際には
職位を使うこともできます。
例文
"My mate up and left his waiter's job today."
私の友人が今日ウェイターの仕事を
辞めた。
To walk out = 離れる、突然又は怒って辞める
突然辞める、急にいなくなる、
立ち上がって行く、凄い勢いで出ていく
立ち去る、押しのける、出て行く、
いなくなる
例文
"He had walked out in a temper"
激怒して彼は出ていった。
To up and leave =経路を動く、
進む、場所から出ていく、
立ち去る、ある経路を進む、
ある手順に従う
My friend pulled out of his job at the restaurant yesterday.
My buddy just walked out of his job at the restaurant yesterday.
▪ My friend pulled out of his job at the restaurant yesterday.
To pull out is to quit or resign.
This means that he/she quit the job and left.
▪ My buddy just walked out of his job at the restaurant yesterday.
Walked out is to leave the job because of being either unhappy or want to do something else.
This sentence indicates the he/she has decided to quit quickly and leave that job.
・My friend pulled out of his job at the restaurant yesterday.
To pull outは、辞める・辞任することです。
よって上記のフレーズは、「昨日、友達がレストランの仕事を辞めた。」という意味になります。
・My buddy just walked out of his job at the restaurant yesterday.
Walked outは、その仕事が楽しくない、または何か他のことをしたいという理由で仕事を辞めることです。
この文は、彼/彼女が急いで仕事を辞める決断をし、退職したことを示しています。
My friend resigned from his job at a restaurant yesterday.
To 'quit or resign' at ones job means that your have terminated your job contract with your employer.
'Terminate' means to bring something to an end.
To terminate your job contract means that you have ended your contract at your current job and leave the business/company.
To 'quit or resign' at ones jobは、自分の雇用主との仕事の契約を終えたという意味です。
'Terminate'は何かを終わらせるという意味です。
To terminate your job contractは、現在の仕事の契約を終え、仕事/職場を離れるということです。
When we say someone left their job, it is another way of saying they quit. If you leave a job, you don't plan on going back to it.
"I want to leave my job".
"Are you planning on leaving?"
You can also say 'he quit the restaurant/bar/shop/etc'. You don't necessarily need to say quit his job.
誰かが自分の仕事を辞めたと言うとき、leave a job（仕事場を去る）または、they quit（仕事を辞める）と言う事ができます。
この表現は仕事を辞めて、もう戻る意思がないことを意味します。
例："I want to leave my job". （仕事辞めたい）
"Are you planning on leaving?" （仕事を辞めるつもりですか？）
また、quitの後に必ずしも` his job`（彼の仕事を）とする必要はなく、
以下の様に辞める職場を言うこともできるでしょう。
'he quit the restaurant/bar/shop/etc'
"He left his job at the restaurant." This explains that he quit his job at the restaurant so will no longer be working there.
"He quit his job yesterday at the restaurant." This is another way of explaining that he will no longer be working at the restaurant anymore.
“He left his job at the restaurant.”
(彼はレストランでの仕事を去りました。)
これは、彼がレストランでの仕事を辞めて、
もうそこでは働いていないということを表しています。
“He quit his job yesterday at the restaurant.”
(彼は昨日レストランでの仕事を辞めました。)
これももうレストランでは働いていないということを表す方法です。
After a just few weeks working at the restuarant...he "threw in the towel"...and left!
"Threw in the towel"...is an Idiom:-D which originates in the sport of boxing!
During a match... whenever a fighter's team ("corner") decided that their fighter
"has had enough" and it was time to "give up", they would actually
throw a towel into the ring...Hence "He threw in the towel!"
“threw in the towel” (諦める)
これはイディオムで、ボクシングが由来です。
試合の間、競技者のチームがその競技者がもう十分であったり、
諦めたりするとき、実際にタオルをリングに投げていました。
そのことから：
“He threw in the towel.”
(彼は途中で諦めました。)
He no longer works at the restaurant as of yesterday.
This is a way of telling someone that somebody who know who is a male no longer works at a restaurant because he decided to quite his job the previous day.
イギリス 
南アフリカ 
