Well, 10 words is a good target length, 10 to 20 words is okay.

十个单词是一个比较好的长度，10-20个单词也还可以。

I think it's a good length of time to perform if you're not a really well known band.

我认为如果是不太知名的乐队，半个小时是最合适的表演长度。

This is a good length to aim for.

这个回答的长度对要达到的目的来说是不错的。

Okay, I really think that's a good length for your face shape.

马克：好吧，我真的认为这个长度很适合你的脸型。

I'm not much of a math teacher, but I think this one came out to like 295 words in total which is a good length.

我不是一个数学老师，但我认为这篇文章总共有 295 个单词，这是一个不错的长度。

A good rose is a perfect one, which is free of any diseases or any pests and is of good length and a good stem width.

好的玫瑰是完美的玫瑰，没有任何疾病或害虫，长得好，茎宽好。