Casual speech patterns and slang in any language is rich, diverse, and constantly evolving so it’s difficult to really pin down “rules” on how to learn it. It’s best to pick it up by ear as you gain experience with conversation practice. For the beginner however, it can be quite confusing to read or hear slang that can’t be found in the dictionary.
In this section, we’ll take a look at some patterns in order to understand many common types of slang.
Using 「の」 vs 「か」 for questions
One common area of confusion is whether to use 「の」 or 「か」 to ask questions in casual speech. Previously, we learned that 「の」 is used to ask for or give additional explanation. This is the same for both polite and casual speech.
Example
- 今から時間ありますか。
Do (you) have time from now? - 今から時間ある？
Do (you) have time from now?
- 今から時間があるのですか。
(Why do) you have time from now? - 今から時間があるの？
(Why do) you have time from now?
「か」 on the other hand, is very different when used in casual speech from what we’re used to in polite speech. It’s often used to either confirm something, make a rhetorical question, or show disbelief or doubt. In order words, it’s rarely a real question at all. It’s also more rough and masculine in tone.
Example
- そんなこと、俺が知るかよ？！
Like I would know that kind of thing! - これで本当に大丈夫か？
Is it really ok with this? - まあ、いいか。
Ah well, whatever, (it’s) fine. - もう遅いし、そろそろ帰るか。
It’s already late so shall (we) go home soon?
In conclusion, if you want to ask an actual question in casual speech, you’ll most likely want to use either 「の」 or just a rising intonation.
Shortening /r/ sounds to 「ん」
Many sounds get shortened or slurred together in slang just like any other language. For Japanese, the /r/ sounds in particular often get slurred into 「ん」. This is definitely a useful pattern to be aware of as it will make sense of a lot of words you wouldn’t normally find in a dictionary.
Example
- よくわかんない。（from 分からない）
(I) don’t get really get it. - ちょっと、そこをどいてくんない？（from くれない）
Hey, can (you) move from there a bit? - 何してんの？（from してる）
Whatcha doing?