Yes it can be.
To deplete something is an action and therefore a verb.
deplete
Verb.
There are many synonyms for the word "deplete". And here is a whole bunch of them: Empty, extinguish, use up, reach zero, out of stock, finish and even more. But those should get anyone through an essay or work paper. If not, get a thesaurus from Amazon.
Deplete
Sometimes chemotherapy can deplete a patient's energy.
The word "drain" can function as both a noun and a verb. As a noun, it refers to a pipe or channel that carries away liquid, while as a verb, it means to remove liquid from something or to deplete resources. The context in which it is used will determine its part of speech.
reduce, exhaust, decrease, lessen
Borrow. Deplete. Delete. Destroy.
Tire, exhaust, consume and deplete.
If you deplete the resources on an island, you would be forced to move to find more. Continued use of fossil fuels will deplete the existing supplies in a less than a century.
the word were is a LINKING VERB.
The word 'be' is indeed a verb.