As I understand it, an opener is ANY word that starts a sentence. When looking at VCOP, the idea is to steer children towards using sentence openers which, by their nature, lead to more sophisticated sentence structures. eg. Starting with an 'ing' verb, like "Crawling" could lead to a sentence like "Crawling on my stomach, I tried hard to squeeze under the hedge." Starting with an adverb (like Abruptly in your example) can also be an interesting way to start a sentence. You are right that connectives (words used to join two sentences or two clauses, eg. as, when, if, although..) can be used as openers, eg. 'WHILE' we were waiting, we ate our crisps, instesd of We ate our crisps 'WHILE' we are waiting. If you want some more examples, it's worth looking in the resources section on here...if I remember rightly there are some good VCOP resources available to download, with examples of words children should be using at different levels. Hope that helps!