we must _(派；寄)for the doctor at once

we must _(派；寄)for the doctor at once must i see a doctor at once? no, you___see a doctor for the Must we go to see a doctor at once when we have the flu?Yes, Her mother is ill,we must ___a doctor at once. the letter _ _(must post) at once 被动语态 He's badly hurt ,we must send_____a doctor at once.A.to B.up mother is seriously ill .we must （）a doctor at once . --we must call the doctor.--yes,we must .[do] must we ____(start)the work at once ?求详细讲解 讲方法 the doctor suggested the man have an operation at once The doctor says that he will come at once The doctor insisted that he _____somking at once.