1. There's a car ahead of Brian's car, but it isn't moving.

(ahead of = in front of)

 2. It's a good idea to get your work finished ahead of time.

(ahead of = before)

 3. His ideas about science and technology are ahead of everyone else's.

4. Sergio is thinking about the week of vacation that he has ahead of him.

 6. Marcia and her coworkers are trying to stay ahead of the competition.

 7. Victor wants to stay ahead of the other students, so he works very hard on his school work.