What is the passive verb in this sentence? Wind turbines *provide* them with a great source of clean energy. Is "provide" a passive verb?
"Provide" is a passive verb if you change the sentence.
In order to make "provide" a passive verb, we must change the sentence. In passive sentences, the thing receiving the action is the subject and the thing doing the action is optionally added at the end of the sentence. So, in making "provide" a passive verb, the sentence will look like:
A great source of clean energy is provided by wind turbines.
Hope this helps! :)