It’s important to know how to get what you want. When you go to another country this is especially true. It’s a good idea to try to be polite when you do this with people you don’t know or even with people that you do know. If you are studying Japanese, you need to learn a little more than just a magic word. There is more than one way to say please in Japanese and it effects the grammar of the sentence but it shouldn’t be too difficult. Let’s take a look at three different ways to say “please” in Japanese
The most common and useful way to say please in Japanese is by ending a sentence with kudasai. This is used in both casual and formal situations and is the most flexible way to say please. We can’t just throw it at the end though, we need to change the verb to the -te form. If you cooked a nice dinner and want to invite your friends to eat the feast in front of them you can say “食べてください” or “Please eat”. We take the word taberu and change it to the te form and add kudasai. Not too hard, right? If your friend gets a little too drunk and starts to tease you about your bosses crush on you, you can tell them 「やめてください！」 or “Quit it”! I use kudasai for all of my pleases except for in super formal situations and when I make very very casual requests.
Onegaishimasu is much more polite and is used for business occasions and with strangers when you want to be particularly polite. You can also use it as a stand alone word, unlike kudasai, when you just want to say “please”. An example of this would be if someone offers to give you a tour of the city, “Onegaishimasu!” means “please do!” Most of the time this word is used with nouns. We might say to a waiter 「水おねがいします」 or “Can I please have water”. Most people wearing a uniform, be it a suit or a fast food restaurant uniform will opt for this more polite variant of the magic word. You can also use it to someone you don’t know to be polite. A casual way to use this is 「おねがい」but be careful as it sounds a bit more desperate.
Choudai is the most casual way to say please. We may use it in a very casual way with close friends for small requests. 「水ちょうだい」 means “Water please” but you don’t want to say this to a waitress or even to a friend who is older than you as it is very casual. Children often use choudai with their parents if you say it in a childlike voice, it might be considered either really cute or really annoying. While a word for word translation does not reveal it’s nuance, the above sentence could roughly translate to “Gimme water please”. Even with close friends, it’s a good idea not to use this for big requests.
In a country where being polite is so important, it’s important for anyone studying Japanese to learn how to say please.