Lack of errors

I typed the following into the demo box on the web site, and it didn’t show me any errors. Am I doing something wrong, or should I not expect errors/suggestions here?

Does why turtle.
In of tickle.
Dog not why inside three doesn’t.

We optimize LT for real errors (errors that appear in the real world), not artificial ones. Thus sentences that are really messed up sometimes don’t give an error.

Thanks. Do you know of any tool that will tell me if a sentence is grammatically correct or not, even if it’s not a real-world sentence?

Hi Alex,

This is actually a tricky question. There are two kinds of grammatical correctness:

  1. A sentence must be well-formed. “Dog between cat ox new.” is clearly not well-formed because there is no verb. But imagine an answer to the question “For how long have you been working here?”. It could be “Since 1997.” That is a well-formed utterance in the context even though it has no verb.

  2. There are well-formed sentences that are still “agrammatical” in the Chomskyan sense, like the famous “Colorless green ideas sleep furiously.”

Add to that the great ambiguity of the English language (e.g. “can” can be a modal verb, a regular verb or a noun) and you can see that a program able to tell whether a made-up sentence is grammatically correct (both in the first and second sense) would need what’s called world knowledge. We (as in “humanity”) are still far away from that.

That’s why, as far as I know, such a tool as you have in mind does not yet exist. Building it would be the ultimate feat of computer linguistics!