I think her English was not very good. She mispronounced a lot of things and left out a lot of sounds in words. I'm sure it was better than some other certain singers', but I can't think of anyone in particular right now.
Here's why I hate this single:
1. Moon Crying is really boring. I swear it's like the most forgettable ballad I've ever heard. The arrangement is really typical. I've heard this song 100 times before and I'm not impressed.
2. That Ain't Cool is really ridiculously repetitive. It's like the same thing over and over again throughout the whole song with little to no variation.
3. Once Again is kind of nice, and I guess it's something "new", but it doesn't really stand out and I think it's also forgettable.
4. Lady Go! is fun, but that's really all it is.
And all the songs kind of like... don't fit together at all. They're a random bunch of songs to put on a single together. :/