«who, «whom,» «which» y «what» como objetos de preposición

1. With whom did you go?;Who did you go with? To whom were you speaking?; Who were yo speaking to?

[En Inglés formal se usa ‘ «preposición» + «whom» ‘ («With whom did you go?»). En Inglés ordinario se traslada la preposición al final de la frase; y, en lugar de «whom,» se prefiere «who,» («Who did you go with?»)]

2. To which address did you send it? // Which address did you send it to? On what do base your theory? // What do you base your theory on?

[En Inglés formal se usa ‘ «preposición» + «which»/»what» («To which address did you send it?»). En Inglés coloquial se traslada la preposición al final de la frase («Which address did you send it to?»]