He has a sharp eye

Uneliso elibukhali : He has a sharp eye

u: you/he/she

iliso: eye (amehlo: eyes)

bukhali : sharp

This phrase carries the same meaning as the English equivalent (referring to someone being observant or vigilant).

Usefully, the meanings also work in their literal form in isiXhosa - 

amatye abukhali - sharp rocks

Iliso is also the word for 'bead' (assumably because of their eye-likeness)

though people more often talk about amaso : beads

It may be useful to think of the English phrase 'beady eye' to remember the link here!

Grammatically, you can see that the prefix of the adjective is changing depending on the noun.

so :  iliso elibukhali: sharp eye

amehlo amahle : beautiful eyes

abantu abahle : beautiful people

Umntu omde : tall person

The other thing to notice that adjectives come after the noun in isiXhosa, whereas they come before the word in English.