I have had a song stuck in my head for the past two weeks.
This song is titled "Dui Bu Qi," and it is sung by an English band called Transition. They sing it in Mandarin. The main lyrics go "dui bu qi, wo de zhong wen bu hao," which means "I'm sorry, my Chinese is not very good."
My Chinese teacher first introduced it to us a couple of weeks ago. There are a couple of phrases in the song that would come in handy in China. Unfortunately, the song is very catchy.
The weekend after my Chinese teacher introduced it to us, I could not get it out of my head. But that is normal for me. I have had songs stuck in my head before (Lorde's song 'Royals' had a particularly long run), and I figured that some other song would come and replace it. But that's not what happened. We sang it again on Monday, and then I noticed some of my classmates who are in other sections of Chinese start to sing it. Now it's gotten to the point that even if it has been out of my head for a day or so, once I enter the Chinese classroom, I immediately think of the song and then the cycle starts all over again.
Anyway, I encourage you to go listen to that song. If anything else, I guarantee you that by the end of it, you will know how to say "I'm sorry, my Chinese is not very good."