〜しか〜ない

only (and no more)

"Only", stressing that it is less than expected or wanted. The verb is always negative.

Readings

How to form it

Put しか after the noun or number and make the verb negative: 千円(せんえん)しかない (I only have a thousand yen).
が and を drop before しか. Other particles stay in front of it: 彼(かれ)にしかできない (only he can do it).

財布(さいふ)に千円(せんえん)しかない。

I've only got a thousand yen in my wallet.

これは彼(かれ)にしかできない仕事(しごと)だ。

This is a job only he can do.

The verb is negative but the meaning is not: 一人(ひとり)しか来(こ)なかった means one person did come.