Sorry, couldn't think of a better way to describe it. What I mean is to allow certain special 'wildcards' in words, such as [sth.], [smb.] or something along those lines.

Currently I just use 什么 or 谁 but it's not very efficient to constantly write these. E.g. I entered '给谁介绍谁', but it would be great to have '给[smb.]介绍 [smb.]'

Interesting idea but I'm not sure it fits with Skritter's goal of helping students learn how to write Chinese and Japanese. This is more of a grammar issue which Skritter is not trying to teach since it's not a one-stop site for all Chinese learning needs. I would much prefer they spend their time on other issues, like getting iPod/iPhone/iPad support.

I think it's really important to learn vocabulary in context, even if it's just a usage structure. If you want to be able to encode the language this is just as important as memorising vocabulary. Memorising vocabulary alone only lets you decode efficiently.

I totally agree, but I guess the way I view it is that I come to Skritter to learn how to write the specific character, and then I use my textbook, other books I'm reading, my class work, and speaking Chinese with friends to put it in context.

However, now that I think about it, I think Skritter actually already has what you're looking for. For example, you can make the pinyin for a sentence pattern 给...介绍... and then in the definition simply write 给[smb.]介绍[smb.]. That way when it pops up for you to study you will automatically know you are studying the sentence pattern and it will reinforce the pattern in your brain.

I don't think we can put '...' in words or pinyin, can we?

You can't put ... in writings, but you can put them in readings and definitions. So the standard thing that we do is add the words like this:

给介绍
gei3 ... jie4shao4
give ... an introduction to

My bad, I meant to say definition not pinyin.