こう・そう・ああ・どう

こう, そう, ああ and どう say how something is done or how something is: "like this", "like that", "how". They go straight before a verb, with no particle.

• こう – like this, the way the speaker is showing
• そう – like that, the way the listener said or did it
• ああ – like that, something away from both, or that you both remember
• どう – how

そう or ああ

そう points at what the listener has just said or done, or at what was just mentioned. That is why it gives "yes, that's right" (そうです) and "I think so" (そうおもいます思います). ああ points at something neither of you is doing now: a person over there, or something you both saw or heard earlier.

こういう before a noun

Before a noun, the form is こういう, そういう, ああいう, どういう: "this kind of", "what kind of". こう on its own cannot take a noun.

• × こうの本 → こういう本

Usage notes

These go beyond saying how something is done.

どう as "how is it"

どうですか asks how something is, or offers it: "how about".

With なる

With なる, the four describe how things turn out.