The noisy boy ______stand up by a teacher. 

— May we leave the classroom now?— No, you _______. You _______ to leave until the bell rings.

 ----Who’s the little baby in the photo,Susan?  ---It’s me ,this photo       ten years ago.

—Oh, this is really an old building.—Do you know when it        ?

– It’s difficult for the village children to cross the river to get to school.– We think a bridge ________ over the river.