What tense is being used in the following sentences?
I have been here.
How often have you been in love in your life?
There has been an accident.
I think these sentences use the present perfect tense. My first question regarding the first example: Is been being used as a past particle or as a helping verb? If so, my second question is: What part of speech is here?
By the way, I took my first two examples from Michael Swan's Practical English Usage, and the third from a book on grammar by Raymond Murph (all three are covered under "present perfect").