Ask questions about the sentence: the head teacher proposed that we come to his school for 15-20 days in april. how ? !

1) Did the Head teacher propose to us to come to his school in April?
2) Who proposed to come to the school for 15-20 days in April?
3) Where were we proposed to come in April?
4) When were we proposed to come to the Head Teacher's school?
5) How long were we invited to the Head Teacher's school for?