* My coworker and I are working on the presentation together.
* The manager gave my coworker and me a raise.
* My coworker and I decided to take a break for lunch.
* The new project will be challenging for my coworker and me.
Important Note: "My coworker and I" is the correct way to use the pronoun in these situations. "Me" is the object pronoun and should not be used as the subject of the sentence.