—Bob, your room is so dirty. It must ________ every day.
—OK. Mom, I’ll do it right now.
clean
be cleaned
is cleaned
—Mary,I have never seen a zoo that is________for animals to live in. —Neither have I.
—Do you know Amy Hayes? —Of course,I know.She is the woman who built a house________rubbish.
—How much do I need to pay________the dictionary? —About fifty yuan.
As we’re students,we________obey the school rules.
All the students are talking and laughing in the classroom and it’s________.