Verbs may be divided into three types:

A.                 Action verbs - show an action -- either physical or mental




Smith catches the ball. (catches  shows a physical action)

Smith imagines  great things. (imagines  shows a mental action)

Smith  is wearing  good clothes. (is wearing shows a physical action)



B.         Verbs of being (forms of be) - show a state of existence




Smith  is  strange. (is shows a state of existence)

Smith will always  be my friend. (will be shows a state of existence)

Smith has been here for a week. (has been shows a state of existence)

Smith was away last week. (was shows a state of existence)



  C.                              Linking verbs - link a subject with its complement (A subjective complement "completes" / "equals" the subject.)


Linking verbs:


appear, taste, smell, feel, look, sound, grow, seem, remain, become






NOTE:  Most linking verbs can also be used as action verbs.