Having mastered the technology of manned spacecraft, China became the third country in theworld ______ manned spaceflight independently.[ ]

These teenagers don’t know much of the world yet;that’s why they are so easily_____

－It’sdifficult for me to pass the English exams．－So doI．But we shouldn’t hope．

In our school there ______ a number of books on science and the number of them ______ growing larger and larger.

Yes, please. I want a sweater.