Thetiredtravelergotbacktotheroomandfellasleep________(atonce;immediately).

atonce等于什么来着?

.Allthedoctorsinthehospitalinsistedthathe____badlywoundedandthathe____atonce. A: shouldbe;beoperatedon B: were;mustbeoperatedon C: was;shouldbeoperated D: was;beoperatedon