Learn English – If a one person business is supposed to refer to their business as “we”, then how do you do this:

If a clause has all of the following, then it is in the passive voice:

• A form of an auxiliary verb (usually be or get)
• The past participle of a transitive verb
• No direct object
• The subject of the verb phrase is the entity undergoing an action or having its state changed

Example: The documents were printed.

Optionally, the agent is expressed in a prepositional phrase with by: The documents were printed by the printer.

There are some exceptions; though, generally speaking, if a given clause meets all the above conditions, then it is certainly passive voice. The Wikipedia article about the English passive voice has a pretty complete coverage, detailing all cases of English passive voice, but the major exceptions are these:

• A passive clause may have a direct object in the case of ditransitive verbs; when the indirect object is promoted to subject, the direct object remains. (Someone gave Mary the documents becomes Mary was given the documents.)
• In concealed passives, the verb form is a gerund-participle and has no auxiliary. (Your document needs printing)
• In bare passives, the auxiliary is missing, but these clauses can only be used as modifiers (With the document printed, Mary could hand in her paper), or in special syntactic constructs like newspaper headlines (Document printed by printer).
• Some related forms, the passival (The document is printing) and middle voice (These documents print well), may be considered to be kinds of passive voice.

You don't normally use Present Perfect with stative verbs (have, be, like, seem, prefer, understand, doubt, know, etc.) Here's a longer list - in general, they apply to states that last for some time.

In some contexts, such as "How long have you had/been having these symptoms?", there's no real difference. Arguably, been having calls more attention to the fact that you're still having the symptoms, but I doubt many people would consciously either make or hear that distinction.

A "rule of thumb" for to have is: when it means to experience, you might want to use Present Perfect; when it means to own, you almost certainly don't.

Here's an example for to be using the "slightly unusual" Present Perfect in a construction which is perfectly valid, and is probably the most succinct way of expressing the intended meaning...

By now the new cook will have been being introduced to her duties for several weeks.