Every time I thinking of helping verbs, I hear the helping verb chant my mother (a 30-year English teacher) taught each new class of 6th graders. I think it must have been original to her; I can't find an example online (though I came up with a similar one sung to the tune of "Jingle Bells.")
Image: helping hands
Were can be either a helping/auxiliary verb or a simple past tense verb of being. What's the difference? Check to see if the sentence includes another verb that goes with the "were."
The poodles were barking. (were + barking = two verbs = helping verb)
The delivery drivers were on the porch. (were + no main verb = one verb = verb of being)
The grammatical function of helping/auxiliary verbs (hereafter called just "helpers") is to add information to the main verb. In the case of "were," a verb of being, the information added tells the reader that the main verb's action (in this case, barking) was a continuous one. Our poodles did not simply bark once and get it over with but instead continued their barking for an extended amount of time at least equal to the drivers completing the delivery.
Deleting all instances of "were" is not necessarily a good idea. Because the barking kept going and going and going like the Energizer bunny, our helper achieves this meaning effectively and succinctly.
Stated more directly: if "were" is paired with a main verb that ends in "-ing" we cannot just drop it without significant alteration to the sentence's meaning and/or intention.
However, we can and should get rid of "were" when it does not serve its function as either a helper or a standalone verb of being. Guess what we call this....🥁🥁🥁
Passive voice.
The delivery drivers were noticed by the poodles. The packages were delivered to the porch by the drivers. The delivery drivers were barked at by the poodles at the window. The poodles were shushed by the owner. The owner was ignored by the barking poodles.
Rearranging sentences written in passive voice not only makes your sentences better, the process automagically* avoids your unnecessary "were."
The poodles noticed the delivery drivers. The drivers delivered the packages to the porch. And so on.
*automagically is not a real word. But don't you agree it should be?