iTunes sending already downloaded songs to the cloud

Every so often I'll look through my songs on my iPhone 5S and see a huge chunk of the songs I have downloaded from iTunes have been sent to the Cloud, meaning I can't listen to or d/l them until I get back on wifi. I'll download them back to my phone and then the same thing will happen again later. How do I keep these songs on my phone?

iTunes sending already downloaded songs to the cloud