しか〜ない
Only …, nothing more (always with a negative)machine translation
FormationNoun + しか + verb in the negative
しか follows a noun and always pairs with a negative form (〜ません, 〜ない). The whole pattern means "only … and nothing more", carrying the speaker's feeling that this is little, not enough.
Compare with だけ: だけ goes with an affirmative sentence and states a fact neutrally, while しか〜ない emphasizes the shortfall. 百円だけあります is "I have 100 yen", while 百円しかありません sounds like "I have only a measly 100 yen".
Note: しか replaces the particles は・が・を entirely — you do not say がしか or をしか.
Examples
財布に百円しかありません。
I have only 100 yen in my wallet.
教室に学生が一人しかいません。
There is only one student in the classroom.
朝はお茶しか飲みません。
In the morning I drink nothing but tea.