1. When we use "阴历", we will not add "号、日“. And the written words should be changed like "一/二/三。。。。。。", but not "1/2/3..." Eg: 今天是12月16日（or今天是12月16号），农历是十一月初六。 A: 我的生日是8月22【号】。 B: 阴历还是阳历？ A: 【阳】历。阴历生日的话是七月初一。你生日是几月几号啊？ 2. 你现在习惯中国的生活吗？=在中国的生活你现在习惯吗？ 你现在【对】中国的生活习惯吗？ 3. 名片 = business car. 你的理解是正确的。 "片子"（片儿）, as usually it means "Adult movie". Eg: 喂，你今天怎么看起来那么困，该不会是昨晚看了一晚上的片儿吧。 谁有岛国（means日本）的片儿，发给我一下呗。。

1) ***Is it OK or incorrect to add 的 at the end of the question -- so, 你是几月几号的？ Yes, it is correct. 2) ***Can I change the order a little bit and say 你现在中国的生活习惯吗？ <--- Would this still be correct? Actually yes, sometimes we speak like this, but it's not standard and we won't write in this way. Anyway, I sugget you to regard it as a wrong sentence. I mean, if you are very fluent in Chinese, it's ok to say so and you'll sounds very casual. But if you are not, it only sounds you are making a grammar mistake. 3) I was taught that 名片 is the word for a "business card". ***Is it true, though, that in some parts of China, the word 片子 is also used? If so, in what region(s) do they say that? I'm not sure if there are people use 片子 to replace 名片. Through my experience, 片子 is usually used to refer to 1.an X-ray film 2.movie or vedio (it doesn't have to be a porn, but it's also truth that many people who see the word 片子 would think of porn) 3.photo (basically only photography lovers would say it, the others just say 照片/相片)