—Must I finish my homework at school?— No, you_____. you can do it at home

Harry is feeling uncomfortable. He _______too much at the party last night.

—Look! It________be the new woman manager. —It________be her.She has just left for Shanghai. 

—What does the sign over there read?—No person ________smoke or carry a lighted cigarette ,cigar or pipe in this area. 

Nobody knows for sure how dinosaurs died out 65,000,000 years ago. It _______ because of sudden changes of their living conditions.