We thought it would be good to let you know what we have been up to in the last few months, besides publishing posts on our website. Well, we have been very busy improving our parser and the conjugators that are based on it. Some of the new features were added thanks to your input sentences, which made us aware of problems we had overlooked.
This article is concerned with a challenge posed to us by negative polarity items when we were developing the Contextors Voice Conjugator. We’ll begin by briefly introducing negative polarity items, and then proceed to discuss their interaction with voice alternation.
The Contextors Voice Conjugator is a tool for changing the voice of English sentences from active to passive and vice versa. It is based on Contextors’ syntactic parser, which assigns to sentences of English constituent structure trees where the nodes are annotated with syntactic category labels and grammatical function labels.
When using the Voice Conjugator to change the voice of a sentence from active to passive, you might find out that there is more than one passive counterpart to your active sentence. This can happen because of one or both of the following scenarios.
When using the Voice Conjugator to change the voice of a sentence from active to passive, you might find out that there are active sentences that don't have a passive counterpart. Intransitive verbs like ‘rest’, ‘dine’, ‘die’, ‘fall’, etc. cannot be passivized at all. Some verbs taking a direct object (sometimes with other complements following it) do not passivize their direct object.
The Contextors' Parser assigns syntactic structure trees to strings of words in English. Developing the parser is a fresh trial of teaching a machine rules about different linguistic aspects of English. In the process of adding rules to the parser and examining its solutions, some interesting theoretical issues arise.