@tommy_san @bunbuku

英語の「better」の比較級が翻訳していませんね。「もっとうまく」か「よりうまく」とかが必要ではないかしら。それとも私が知らない言外の意味でもありますか？

なければ文章を修正するかリンクを断ち切るかの話になりますね。

Even the English sentence isn't so great. There's not enough context. This was likely part of a conversation in which the context was obvious.

Is she better than someone else, or maybe she could sing better after her operation, or now that she is recovering from an illness. Or maybe she's just better than the last time she sang.

We have some better English example sentences with "sing better."

[#294574] He can sing better than any of us. (CK) *audio*
[#58892] You will be able to sing better next time. (CK) *audio*
[#305110] Which of them can sing better? (CM)
[#636287] I hope I sing better next time. (Nero)
[#264348] I expect to sing better next time. (CK)
[#310755] She can sing better than anybody else in her class. (CK)

And I just realized it can also be used to mean "It was okay, but she could sing better", which seems to be the approach the German and Esperanto translations went for.

I read this sentence as "Betty managed to sing well", i.e. she did not make mistakes.