Last week a kid wrote on the office white board "Give me all your cheese now!" and I attempted a translation into Chinese (mostly to practice my handwriting). I wrote 马上给我你的奶酪。 I felt like this translation was lacking emphasis, but I didn't know how to properly add it. I know that 啊 / 呀 is often used in this way, but I'm not sure if it's the correct choice to use here or where to add it. How do I increase the emphasis of this sentence instead of making it deadpan?
Personally, I find Mandarin rather unsuitable for a sentence like this.
(Note that the sentence "gimme yo cheese!" sounds ridiculous in English.)
When I think about the formal nature of standardized Mandarin, I can't help but dream up a sentence like: 请把你的奶酪都给我吧
Of course, this sentence sounds pretty silly, and the 请……吧 pattern has an effect opposite of what you wanted. Ending a sentence with 啊 (or one of its similar sounding particles, e.g., 哎) would do the trick.
As suggested above: 交出你的奶酪啊！ is good.
That said, I think you'd end up with better results if you resorted to a dialect (just like "gimme" is not standardized English).
As a more aggressive alternative in Mandarin, you could try: 赶快把(所有的)奶酪都给老子交出来！
This basically sounds like you are robbing someone for their cheese, which would have had the humorous effect you intended (judging by your described context), but it'd be tough to imagine an appropriate real-life scenario in which to employ this vocabulary.
...Unless you were really trying to rob somebody: 把值钱的东西都给老子交出来啊！
Disclaimer: Don't steal! Don't rob! 构建和谐社会！
I think one challenge with this question is that the original English is kind of a strange sentence, i.e., it's frankly hard to understand in what context someone would actually say "Give me all your cheese now!". I think if you provided a context, it would be easier to propose how to give proper emphasis in Chinese.
For example, let's say a teacher was doing a cheese experiment, and asked all the students to give him all their cheese, and for some reason the students didn't hear or didn't respond, the teacher might say "Give me all your cheese now!" (although even in that case it still sounds a bit strange to me).
In that situation, what needs to be emphasized is that it's a second request, which could be done by prefacing it with something like “我说” or “听到了没有”. How to emphasize this sentence in Chinese is highly dependent upon the context, and the context for this particular English sentence is rather hard to fathom.