Here are some examples of how it's used:
* Surprise: "Jeez, look at the size of that fish!"
* Annoyance: "Jeez, I forgot my keys again!"
* Disbelief: "Jeez, you're telling me you actually ate the whole cake?!"
It's important to note that "Jeez" is still considered somewhat informal and might not be appropriate in all situations. It's best to be mindful of your audience and the context when using this word.