Linking verbs act as an equals sign between the subject and another word in the predicate, showing that the subject "is" or "is like" something else described by a noun or adjective. Common linking verbs include forms of "to be" such as "is", "am", "are", "was", and "were". To identify a linking verb, you can substitute "is", "am", or "are" for the suspected verb - if the sentence still makes sense, it is likely a linking verb. Linking verbs do not show action and instead connect the subject to another word that renames or describes it.