We all know that dinosaurs lived on the Earth more than ______ years ago.

—.What time is it?  — It’s_______________.

There are about ________ students in our school.

—What class are you in?  —I’m in ____, ____.
A. grade seven; class three
B. Grade three; Class seven
C. Class Three; Grade Seven

His mother is ______. Today is his mother’s thirtiethbirthday.
A. thirteen         B. thirty          C. Thirtieth

—Good news! There is ______ a birthday party this weekend．
—Great．I was told it was Mary’s ______ birthday this weekend．

Look ! _________ students are doing morning exercises on the playground .

_____ of the land in that district ______ covered with trees and grass.

--- How many students in your school have lunch at home?
--- Only ________ of us have lunch at home.

---How was your weekend?
---Great! It was my grandfather’s _________ birthday. We enjoyed ourselves.