Dear students.You should try to thank the others if they have done a work for you.But you should always thank and on time.God said :everybody who not to thank my creatures as if do not thank me .(لم یشکرالمخلوق لم یشکرالخالق)(کسی که از مخلوق من تشکرنکند از من تشکر نکرده است)