I don't understand intransitive verbs. ex: the saleslady stood for forty-five minutes. Is this transitive or not?
Intransitive verb needs not any object. In this context "stood" is an intransitive verb.
Stand verb is both tra/intr
Many verbs are transitive ( need object) or many are both tran/intr.
Some common verbs are only tran.
Like, discuss, imply, raise
Some common verbs are intr.
like, cry, rise etc.
Bring, wish etc
Problem is we don't know which one which!
I discussed the issue in Applied linguistic forum to LinkedIn few years ago where many famous English grammarians usually have been roaming for exchanging our views.
No, nobody said it has any good rule to identify the specific one unless we practice them in our mind day by day!
Play with a good dictionary.