This question already has an answer here:
I have been at interviews at company A and B. Today i received a verbal offer from company A, but they said that I would probably not receive the contract before 3 weeks time. I have no preference between A and B. How should i react if company B also offers me a job? I think it would be very dishonest to say yes, as I have already said yes to company A. But I feel a bit uncertain as I don't have anything in paper. I think that it is very unlikely that company A will not follow through as it is a very well respected company, but I of course can't know for certain. I also have an interview at company C next week. Should I cancel this interview now? I would rather work for A than C.
I don't know if it relevant, but none of these jobs are full-time positions. I'm a 20 years old university student.