First, let me say that this use of 'sham' as a transitive verb is uncommon. When it is used, it often (although not always) refers to an activity. I've come across he shams crazy Don't use it like this with an adjective.
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Russkiy BearI know pretend is more common.Even "feign" is more common. The verb "sham" does not exist in my dialect, and I can't remember ever seeing it in print.