Question

Another possible diagnosis included pulmonary embolus.
which words are verbs?
pulmonary embolus = verb

The external oblique fascia was then incised, and the incision was lengthened in the direction of the fibers using Metzenbaum scissors.

was incised = verb
was lengthlened = verb

Answer 1

first sentence -- incorrect guess about the verb

second sentence -- both verbs are correct (Did you guess? Or are you choosing after thinking?)

http://www.chompchomp.com/terms/verb.htm

Answer 2

Well, trying to remember which is which. Long time since I have done any Grammar and I am pretty exhausted right now haha.
Read in book that says Other verbs indicated a condition.
diagnosis = verb

Answer 3

Verbs fall into two main categories:

Action verbs -- things you can DO
~~walk, talk, think, consider, believe, use, include, exclude ...
http://grammar.ccc.commnet.edu/grammar/verbs.htm

Linking verbs -- forms of "to be" (am, are, is, was, were ... ) and a few others:
http://grammar.ccc.commnet.edu/grammar/verbs.htm#linking