这是一首情诗。

Zhè shì yì shǒu qíngshī.

This is a love poem.

他为她写了一首诗。

Tā wèi tā xiě le yì shǒu shī.

He wrote a poem for her.

这首诗写得太美了。

Zhè shǒu shī xiě de tài měi le.

This poem is written so beautifully.