仕事を３つも…忙しい！
I'm juggling three jobs.
＝仕事を３つ掛け持ちしています。
もちろん「I have three jobs at this moment」と言って通じないことは無いですが、ここでは特に、掛け持ちをしている”てんやわんや感”を出したいですよね。そこで、英語圏でよく使うのが「juggle」という言葉です。
Jugglingといえば、あの、ボールをいくつも空中で回し続けるジャグリングを想像するかと思いますが、まさにその通り。ボール（=[仕事](https://eikaiwa.dmm.com/uknow/questions/37171/))をいくつも、[次から次へと](https://eikaiwa.dmm.com/uknow/questions/34931/)回し続ける様子で、日本語の所謂「掛け持ち」を表現します。
Don't push yourself too hard, though!
（無理しすぎないでくださいね！）
[「副業」](https://eikaiwa.dmm.com/uknow/questions/4400/)なら a side/second job などと言いますが、３つ掛け持ちの場合は以下のような表現がいいかと思います。
I work at three places.
（３カ所で働いている。）
I have three jobs.
（[仕事](https://eikaiwa.dmm.com/uknow/questions/37171/)が３つある。）
I'm hectic - This gives the sense that you are very busy but still have time to schedule in a appointment/arrangement "I have 3 jobs and all of them are hectic at the moment" This tells people that your schedule is tight but you can make arrangements.
It's manic. - This is to tell people that you have no time at all "It's manic at work, I'm completely shattered". This will tell people there is no free time in your schedule available.
I'm shattered - This will tell people that you are very tired and need rest. Imagine a glass window that has been broken (this is yourself) you would say "I'm shattered from working 3 jobs, I'm just going to rest"
If you would like to express to someone that you are working 3 jobs, you can say something like "I am working 3 different jobs right now" or "I am employed at 3 different places currently.". This is an easy way to express that you work 3 jobs to someone.
1. To hold down a job = to manage to keep a job for a period of time.
2. Work one's butt off = SLANG - to work very hard
"My father worked his butt off to pay for our education."
'Butt' may also be replaced by: arse or backside.
"John works his backside off down at the factory."
1. To hold down a job =仕事を一定期間キープすること
2. Work one's butt off = スラングで、精一杯働く、死ぬほど働くこと
例："My father worked his butt off to pay for our education."
父は僕たちの学費のために死ぬほど働いた。
'Butt'の代わりに、arseやbacksideが使われることもあります。
"John works his backside off down at the factory."
ジョンは向上で精いっぱい働いている。
First, you can use the verb "have" to show that you possess three jobs.
It is also possible to use "have got", due to the fact that it is a possession.
Do not use continuous verb form with "have" when it is being used for possession, though.
Secondly, you can also using the verb "work". You can express that you work at three different places, but this is not entirely accurate, because it can also mean that you have one job, but that you work at three different places. So, be weary of that.
まず初めに、三つの仕事をもっていることを説明するのに'have'という動詞を使います。
所有しているという意味の'have got'という言葉も使えます。
ただし、所有していると言う意味で'have'を進行形で使ってはいけません。
二つ目に、'work'という動詞も使えます。
'work at three different places'と表現することもできますが、これだと完全に正しいとは言えません。
なぜなら、一つの仕事をしているが、働いている場所が三つあるということになります。これだとへとへとになってしまいますよね。
I have enough on my plate right now, working 3 jobs.
I am over-schedules at the moment, with 3 part-time jobs.
I am afraid I could not possibly take on any additional work (or projects, or responsibility) since I am working 2 part-time jobs, in addition to my full-time job, trying to get out from under all of this school debt.
例文
I am afraid I could not possibly take on any additional work (or projects, or responsibility) since I am working 2 part-time jobs, in addition to my full-time job, trying to get out from under all of this school debt.
私はおそらくもう仕事（またはプロジェクト、責任）を追加で引き受けることはできないと思います。
なぜなら、私は学校のローンから解放されるためにフルタイムの仕事に加えて２つのパートをしているからです。
I am knackered, I work at three different places at once.
"I work at 3 different places" and "I have 3 different jobs" are both portraying that you are working 3 jobs at the same time. The word "knackered" means that you are tired. This word is an English slang word and should not be used in formal situations. If you want to, you could replace it with "tired" or, better yet, "exhausted". I put this sentence here in case it comes up in a conversation, for example:
"Do you want to join us for happy hour?"
"No thank you! I am knackered, I work at three different places at once!"
You can use any of these natural phrases :
I have three part-time jobs.
Currently, I'm working at three jobs.
I have three jobs.
I am working at three different jobs.
I have three part time jobs that I do.
I work at three places.
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