精品一区二区免费在线观看_国产精品久久久久久av福利软件_97成人精品区在线播放_国内成人精品一区

—Listen ! Helen is singing in the next room．

—It _______ be Helen．She has gone to Beijing．

A．can’t           B．mustn’t        C．may           D．should

——Listen! Helen is singing in the next room．

——It           be Helen．She has gone to Beijing．

A．can’t                   B．mustn’t                C．may                       D．should．

－Listen! Helen is singing in the next room.

－It ________ be Helen. She has gone to Beijing.

[　　]

—Listen！Helen is singing in the next room.
—It _____be Helen .She has gone to Beijing.

—Listen！Helen is singing in the next room.

—It _____be Helen .She has gone to Beijing.

A．should            B．mustn’t          C．may              D．can’t