We can never expect bluer sky unless we create less polluted world.
| A．a; a | B．a; the |
| C．the; a | D．the; the |
I toured Jiu Zhai Gou, I was deeply impressed with its beautiful scenery.
| A．For the first time | B．At first |
| C．It was the first time | D．The first time |
The world seven continents and four oceans.
| A．makes up of | B．makes out of |
| C．is consisted of | D．consists of |
form the moon, our earth with water .seventy percent of its surface, appears as a blue ball.
| A．seen, covered | B．seeing, covering |
| C．seen, covering | D．seeing, covered |
The foreign guests, by an interpreter, came out of the hall.
| A．following | B．to follow |
| C．followed | D．to be followed |
Einstein was usually his scientific study that he even forgot to eat.
| A．very absorbing | B．very absorbed in |
| C．so absorbed in | D．such absorbed in |