I am not sure what you mean by "formal verbs".Phrasal verbs are very common expressions in the language.They don't really compete with simple verbs.WE just use whichever is suitable for what we wish to say.For example if I want to talk about an airplane I will say " The plane takes off at 10.00" . I don't really have a simple verb which can replace it correctly- either depart,leave or something it isn't the correct verb for this context.

All you can say is that phrasal verbs are almost always OK in informal settings and some are also OK in formal settings like business. Sadly there's no substitute to learning them one by one in context.

Hello, I would like to apologize to everyone, I just used the formula I saw in a ESL site, but I understand that there is no difference between verbs; they just express an action and that is their sole purpose. Thank you so much!