that's nice dress为什么不加冠词

新概念里的课文,that's nice dress.和最后一句that is a lovely hat!有什么区别吗?为什么一个加冠词,一个没有加呢?

That's a nice that's sounds nice翻译？用于什么情况 That's a nice watch.怎么改为复数句？ if you're just up for a nice chat online that's awesom too! Is that mary ? Right. she's nice and Iike ( )very much That would be nice. that's all. What's that? That's all that's which; that's when 是什么意思啊