"You should go to the doctor."
(second-person "you"; informal)
"Go to the doctor!"
(second-person "you"; formal)
"You all should do the homework(plural)."
"Do the homework(plural)!"
(second-person "you"; formal)
"The doctor says, you should stay in bed."
(second-person "you"; formal)
"The teacher has said, we should always speak in German."
"How should I help the woman?"