* "ks" sound: Like in box, tax, fix, exit
* "gz" sound: Like in exam, exist, luxury, exactly
* "z" sound: Like in xylophone, Xerxes
* "ksh" sound: Like in sphinx, auxiliary
There are also words where "x" has a different, less common sound, like in the name "Xavier."
It's best to learn the pronunciation of a word with "x" based on its context and how it is used in the word.