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Possible Duplicate:
Is "is" an auxiliary verb?

My Mum's bag is blue.

Is is an auxillary verb in that sentence? If not, what part of speech is it?

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marked as duplicate by waiwai933 Aug 31 '11 at 19:11

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

"Is" is an auxiliary verb in sentences like "he is leaving", and "at full moon, she is called by voices from an unknown world". – Cerberus Apr 19 '11 at 1:29

"Is" is a verb of being, also called a "copula".

copula |ˈkäpyələ| noun Logic & Grammar a connecting word, in particular a form of the verb be connecting a subject and complement.

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Yep. It's also called a linking verb in some circles, including my old latin class, funnily enough. :) – kitukwfyer Apr 19 '11 at 1:17
In your example sentence, it is also the main verb (as opposed to being an auxiliary verb). – PLL Apr 19 '11 at 2:12
@PLL: Hmm, what is the definition of main verb? I gather it is not the same as a finite verb? Is it any non-auxiliary verb? – Cerberus Apr 19 '11 at 12:20
Towson Education distinguishes (I believe wrongly) between 'verbs of being' and 'linking verbs': it muddles semantics and syntax more than is often the case. AHDEL attempts to distinguish the 'existential' main-verb usage (v.intr. 1. To exist in actuality; have life or reality: I think, therefore I am.) from the copular, linking, main-verb usage (Mum's bag is blue / a doozie). Collins places constructions with locative complements (Bill is here) in this category. Auxiliary usages are very different. – Edwin Ashworth Sep 1 '14 at 8:03