You do not have to speak much Japanese to live here comfortably. There is no doubt that Japanese is complicated, but that doesn't have to be the case. Any Japanese that you know and more importantly can use will be extremely helpful. If you arrive in Japan with little or no Japanese, you will find that patience and observation will help you pick up vocabulary, phrases, and communication customs quite quickly.
If You Want to Learn Japanese
Living in Japan is the ultimate opportunity to acquire Japanese in a natural way, like a child would. This is a matter of opening your ears and eyes to the language happening all around you and applying yourself. Intentionally choosing activities and environments that force you to be around Japanese people and communicate with them is a key factor. In this way, linguists agree that acquisition can occur at first with baby words and later through building and adding fluency. Some people have the idea that they must master 1,000 kanji characters or pass a certain level on the Japanese Language Proficiency Test in order to be a successful Japanese user, while nothing is farther from the truth. In some ways, this is a defeatist idea because giving up becomes easy when a person finds that studying by the book is too hard for them. So, the idea of trying to acquire the language rather than learning a boxful of kanji becomes a very attractive strategy, and it is much easier to accomplish without a formal classroom, a trained teacher, expensive textbooks, or a BA in Japanese. With a focus on acquisition, children at school, teachers, older people in town - almost anyone becomes a teacher, with the whole country as your classroom.
The Japanese writing system consists of three different character sets: Kanji (several thousands of Chinese characters) and Hiragana and Katakana (two syllabaries of 46 characters each, together called “Kana”). Japanese texts can be written in two ways: Western style, i.e., in horizontal rows from the top to the bottom of the page, or traditional Japanese style, i.e., in vertical columns from the right to the left side of the page. Both writing styles exist side by side today.
Basic Japanese grammar is relatively simple. Complicating factors such as gender articles and distinctions between plural and singular are almost completely nonexistent. Conjugation rules for verbs and adjectives are simple and almost free of exceptions. Nouns are not pluralized at all or changed in any way.
In comparison with other languages, Japanese has relatively few sounds, so most learners have little problem with pronunciation. The biggest difficulty is accents, which do exist but to a much lower extent than in Chinese. In addition, there are relatively many homonyms, i.e., words that are pronounced the same way but have different meanings.
Levels of Speech
Different words and expressions are used when talking to an unknown person or superior, as opposed to when talking to a child, family member, or close friend. For instance, there are more than five different words for the English pronoun "I," which are used depending on the context. For formal situations, an honorific language level called “keigo” is still in common use.