different ways to say you want something or to do something

In Japanese, there are different ways to say you want something or to do something.

Ga hoshii がほしい

This form allows you to express that you want something. It has to be an object or material, with the only exceptions that time and holidays can be used as well.

Hoshii can be used in past tense and negative form like a i-adjective : Hoshikatta , Hoshikunai, Hoshikunakatta.

For example :

Watashi ha atarashii kuruma ga hoshii. 私は新しい車がほしいです。I want a new car.

Watashi ha jikan ga hoshikatta desu. 私は時間がほしいです。I wanted time.

Watashi ha tomodachi ga hoshikunai desu. 私は友達がほしいです。I don’t want friends.

Watashi ha jitensha ga hoshikunakatta desu. 私は自転車がほしくなかったです。I didn’t want a bike.

Rule

Ga hoshii is a grammar that can only be used to describe YOUR feeling. You can not use this grammar to speak about someone else’s feeling.  

For example, you can not say : Anata ga hoshii or Kare ga hoshii.

Tai form

This form allows you to change a verb so you can express that it’s what you want, or not, to do.

Take the verb in the MASU form (ikimasu), take the MASU away and add TAI desu (Ikitai desu).
For the opposite, take the TAI form (ikitai), and modify it like you would with an i-adjective, by removing the i and add KUNAI desu (ikitakunai desu). The same goes for past tense.

For example:

 Ryokou ni ikitai desu. 旅行にいきたいです。I want to go travelling.

Sushi ga tabetakatta desu. すしが食べたいです。I wanted to eat sushi.

Hatarakitakunai desu. 働きたくないです。I don’t want to work.

Nanimo shitakunakatta desu. なにもしたくないです。I didn’t want to do anything.

Read more: http://www.linguanaut.com/japanese_grammar_23.htm#ixzz2s7As3LTN