iOs 7 dictionaries don't stay downloaded.

I am using an iPod Touch 5th generation with iOs 7.0.2. I frequently use apps and documents with Japanese language content. If I highlight a word and go to "define", it will only bring up the English language dictionary, which naturally has no results for foreign words. I can then go to "manage" and download the Japanese-English and Japanese dictionaries from the cloud, exit the definition screen, click "define" again, and then I will get entries, but I have to repeat this entire download-exit-retry process every single time I want to highlight and define a word. It seems to me that the dictionaries should stay downloaded once I download them! Ideally, I'd like to be able to just have the definitions from the Japanese and Japanese-English dictionaries appear automatically in the "define" screen. Does anyone else have this problem, or know how I can fix it? I'm very pleased that Apple is letting us use multiple dictionaries in the define screen, but it seems a bit pointless if I have to re-download them every time I want to use them.