The faculty and administration of Brooklyn College support an environment free from cheating and plagiarism. Each student is responsible for being aware of what constitutes cheating and plagiarism and for avoiding both. The complete text of the CUNY Academic Integrity Policy and the Brooklyn College procedure for implementing that policy can be found at this site: http://www.brooklyn.cuny.edu/bc/policies.
Strictly your own means that you did it all yourself. That you didn't get your friend to do it for you, and you didn't just copy it, or chunks of it, from the Internet.
If I start to suspect that you are not doing your own work, I will ask you to come see me so that we can discuss the matter. If you cannot convince me that my suspicions are unwarranted, then I will have to send your case to a disciplinary committee that has the right to expell you from Brooklyn College.
Please, let's not go there. I've been there before, and believe me, it's not fun for any of us.