Sam and Eric are in Class One. ______are good friends.
Mr. Black is strongly _______keeping animals in the zoo, because he thinks animals should also have the right to enjoy freedom.
The number of the students in our school is about nine ____. ____ of them are boys.
—Do you think yesterday’s math problem was difficult? —Yes. I could ________ work it out.
—What’s the low-carbon life style like? --Save_______ energy, produce ________ carbon.
—Which of the caps will you take? --I’ll take _______,one for my father ,the other for my brother.