The answer is an adverb clause because "have been" is considered an adverb clause...
I like swimming with my sister in the pool. I enjoy swimming to the bottom and touching the pool floor. I enjoy floating from the bottom to the top of the pool. We also like doing flips into the pool.
Answer:
I'm sorry what are you trying to say
Lifeguards must have current CPR, First Aid, and AED certifications.
