Japatan
Formação
- N／数量 + だけ
- N／数量 + しか + V（否定の形：〜ません・〜ない）
Explicação
Both mean "only." だけ simply limits something and can be used in a positive sentence: 百円だけ あります (I have just 100 yen). しか must be used with a negative form, but the meaning is still "only"; it adds the feeling that the amount is small or not enough: 百円しか ありません (I have only 100 yen). が and を may be dropped after だけ, and しか replaces が and を: 水しか 飲みません.
Exemplos
今朝は コーヒーだけ 飲みました。
This morning I only had coffee.
この 店は 日曜日だけ 休みです。
This shop is closed only on Sundays.
教室に 学生が 一人しか いません。
There is only one student in the classroom.
昨日は 三時間しか 寝ませんでした。
Yesterday I slept only three hours.
Observações
Never use しか with a positive verb (not 百円しか あります). The verb is negative, but the meaning is "there is only a little." だけ with a negative verb means something different: 肉だけ 食べません means "Meat is the only thing I don't eat."
Gramática relacionada
Miniquiz
1私は 朝 パン（ ） 食べます。ほかの 物は 食べません。
Resposta e explicação
Resposta: 2 だけ
"I eat only bread in the morning. I don't eat anything else." The verb 食べます is positive, so だけ is correct. しか needs a negative verb, や must join two nouns, and も does not match the second sentence.
2冷蔵庫に 卵が 一つしか（ ）。
Resposta e explicação
Resposta: 4 ありません
"There is only one egg in the refrigerator." しか must be followed by a negative, and an egg is a thing, so the verb is ありません, not いません. The sentence means there is one egg, and that is very few.
3A「漢字を たくさん 知って いますか。」
B「いいえ、少し（ ）。」
Resposta e explicação
Resposta: 1 しか 知りません
A asks "Do you know many kanji?" B answers "No, I know only a few." しか takes a negative verb, so 少ししか 知りません is correct. しか cannot be followed by the positive 知って います, and the other two choices are not natural Japanese.
