French language Q&A Forum

Would it be correct to use the three-layer structure I wrote down below, when building sentences with double pronouns? Imagine it like a matrix with three columns:

ME, TE, SE, NOUS, VOUS   |   LE, LA, LES   |   LUI, LEUR

Ex  Nous vous | les envoyons demain. | e_m_p_t_y

Ex  e_m_p_t_y | Je la | leur explique clairement.

Ex  Je vous | la donne. | e_m_p_t_y

Ex  e_m_p_t_y | Je la | lui donne.

Where to use vieux and vielle and naveau and nouvelle 

I answered like this, il le lui a refusé? Il le nous a refusé aussi, I was wrong. What went wrong, please? 

In a search to demystify the difference between savoir and connaître, I stumbled upon an article earlier that suggested something along the lines of "use connaître when you've had prior experience with something" with one of the examples being "vous connaissez [name of place]?" meaning have you been to [name of place]? instead of asking whether the person is aware of the existence of said place. The second example was "Je connais Brad Pitt"; a statement that implies that one has met Brad Pitt before rather than plainly saying that they know of the existence of him. Since this lesson hasn't mentioned anything regarding what I've said above, can anyone enlighten me on this matter? 

Not really related to the lesson at hand, but in the example, isn’t besoin supposed to be followed by de?

Les chaussures dont tu as besoin sont dans le placard 

But when is it Avoir vs Etre? I cant seem to learn the rule for this