Lesson 21: Wanting with おう/よう, たい, and ほしい
In this section, we're learning three of the ways that japanese expresses desire.
The "volitional" form, おう/よう, says that you want to or will do something, or invites volition in other people like "let's X". It's also used in compound constructions about volitional action. The volitional form of five-form verbs is -ou, and the volitional form of one-form verbs is よう. It's pronounced with a "long o", not お plus う.
行こう Let's head out.
行こうか How about we go?
食べようと思う I think I'll eat.
With copulas, it usually "invites an idea", like conjecture or possibility.
いいでしょう It's good, don't you think? (おう form of です)
犬だろうと、猫だろうと、なんでも問題ありません Perhaps dogs, perhaps cats; whatever way, there's no problem. (おう form of だ, contraction of であろう> )
The second way to express desire is たい. たい is an い-adjective that attaches the same way as ます. Like てある, たい turns the phrase intransitive.
死にたい I want to die.
アイスが食べたい I want to eat icecream.
(metaphorically "icecream is wanted to be eaten")
Despite making the verb become intransitive, spoken japanese can use を with たい. This is sometimes considered incorrect, but it doesn't feel wrong. The one that logically wants to do the action can't be marked with を.
昨日は君がタイヤキを食べたいと思う I thought yesterday you wanted taiyaki.
(metaphorically "yesterday, you were wanting to eat taiyaki")
たい can go at the end of entire phrases that retain their full internal structure. This applies to a lot of other verb forms too, like てある, but たい is hard enough that this should be pointed out directly.
The final way of wanting is 欲しい ほしい, an い-adjective meaning "wanted".
アイスがほしい I want ice cream (metaphorically "ice cream is wanted")
ほしい is also used as an auxiliary adjective (just like an auxiliary verb) meaning that you want something to happen. If you include the agent that you want to do the thing, you usually mark it with に.
あなたに英語を教えてほしい I want you to teach me english.
てほしい can also be used like the below example. This isn't the only situation where が can be used with てほしい.
じゃあ今、私が何してほしいかわかる？
Well then, understand what I want you to do now?
Be careful to make sure that the が is actually marking the first person in cases like that. In the following example, が marks the subject of a relative clause, not the subject of the main verb with ほしい on it.
そなたが見た事を伝えてほしい
I want you to convey what you saw on your end. (crappy translation)
Supposedly, が can mark the agent of the desired action in more situations than this, but I haven't found any examples.