Simple Examples:
* excellent
* example
* exchange
* expect
* explain
More Complex Examples:
* exaggerate
* excursion
* exhibit
* exodus
* extraordinary
Examples with Specific Meanings:
* ex-husband (former husband)
* ex-wife (former wife)
* ex-employee (former employee)
* ex-president (former president)
Phrases:
* except for
* exactly what
* exactly how
* express yourself
These are just a few examples, and there are many other words and phrases that start with "ex." The best way to find more is to simply think of words or phrases that have a specific meaning and see if "ex" could fit as a prefix!