Everyone knows that _____ sun is in the center of the solar system（太阳系）

–Who is ___ boy in a red cap?  --He is Tom. He is good at playing ____ basketball.

There aren’t __________ girls in the classroom.

Look! There is _____ colour bird in the tree. ______ bird is singing.

Though he is _____ ugly boy, yet he often comes _____ first in the exams.