In the phraseThe koala bears have climbed eucalyptus tree is an action verb or a linking verb?

The verb in the phrase "The koala bears have climbed a eucalyptus tree" is "have climbed". This is an action verb.

Here's why:

* Action verbs describe an action that the subject performs. In this case, the koala bears are performing the action of climbing.

* Linking verbs connect the subject to a noun or adjective that describes it. Examples of linking verbs include "be," "seem," "appear," and "become."

Let me know if you have any other verb questions!