Thanks so much for the responses, Karen and Square!
Hmm. I would propose the a 'label' differs from a 'description'. 'I feel hungry' describes how you feel. 'I
am hungry' labels you. Also, 'I play football' describes your activity. 'I
am a football player' labels you.
I don't see e-prime as something that qualifies labels, so much as something that opens up the opporunity to make them obsolete. Having said that, I know that one can easily say "I see a carpenter" in e-prime. I still consider that an "is of identity" kind of statement though.
And I reaffirm that I do see a difference in using a verb to describe something ("that leaf has/shows/looks green" or "I see a green leaf") and using an adjective to label or define something ("that leaf
is green").
Square, I'd like to hear more about your assertion that languages without "to
be" use a similar substitution method to Russian.