Gustar-type predicates: 好き・嫌い・分かる・できる・ほしい・上手 take が

Why ‘me gusta’ helps and ‘I like’ hurts

In me gusta el sushi and le sushi me plaît the sushi is the grammatical subject and the person is a dative bystander. Japanese builds 好き the same way: 私は寿司が好きです. The liked thing is the subject-like argument, marked が; the person is only the topic, marked は. English I like sushi is the odd one out: sushi is a direct object there, and that is what pushes you toward 寿司を好き. Spanish betrays you elsewhere, though: entiendo el japonés, sé nadar, quiero un coche and tengo tiempo all take direct objects, and their Japanese counterparts do not.

The reason is structural. 好き, 嫌い, 上手 and 下手 are な-adjectives, ほしい is an い-adjective, and 分かる, できる, ある, いる, 要る, 見える and 聞こえる are stative verbs. An adjective cannot take a direct object, and these verbs describe a state that holds of the thing, not an action you perform on it. So the thing takes が.

The cases

Three details that follow

1. Whoever feels it takes は, sometimes には. 私は日本語が分かります. With 分かる, できる, 要る and ある the experiencer can also be 私には, which reads like ‘to me’: 私には分かりません. Two が in one clause sounds heavy, so the person takes は or には.
2. Negation and contrast pull が to は. 寿司は好きじゃないです, 魚は好きですが、肉は嫌いです. This is the ordinary は override, not a second rule. When you see 寿司は好き, nothing broke.
3. ほしい is for things; 〜たい is for actions. 車がほしい, but 車を買いたい. With 〜たい both particles are accepted: 水が飲みたい and 水を飲みたい. With できる the を stays inside the clause: 日本語を話すことができます, because が sits on こと.

Neighbouring mistakes

• 好き is not a verb. 好きます does not exist; conjugate the copula instead: 好きです, 好きでした, 好きじゃないです.
• 分かる is ‘understand’ or ‘can tell’, not ‘know a fact’. For people, places and facts use 知っています; its negative 知りません can sound curt, which is why Japanese speakers often soften to 分かりません.
• 見える and 聞こえる are ‘be visible’ and ‘be audible’ and take が; 見る and 聞く are deliberate actions and take を: 富士山が見えます, but 映画を見ます.
• Praising yourself with 上手 sounds odd. Say できます or 得意です about your own skills and keep 上手 for other people.