Sorry paco, your definition of 'ergative verbs' is different from what I've learnt. I'm a bit puzzled. Let me quote from {{
[link] its definition, just to be sure:
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unaccusative verb (another term is ergative verb):
GENERAL: Special kind of intransitive verb. Semantically, its subject does not actively initiate or is not actively responsible for the action of the verb; rather, it has properties which it shares with the direct object of a transitive verb (or better, with the grammatical subject of its passive counterpart). EXAMPLE: in English 'arrive,' 'die' and 'fall' are unaccusative verbs.
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