Everyone knows that _____ sun is in the center of the solar system（太阳系）
| A．a | B．an | C．the | D．/ |
_____ wonderful time they had in HongKong!.
| A．How | B．What | C．What a | D．What an |
Lily is so smart in her class.She usually spends the_____time and makes the_____mistakes in her homework.
| A．least,least | B．fewest,least |
| C．fewest,fewest | D．least,fewest |
If_____litters,our world will be more beautiful.
| A．everyone | B．someone | C．anyone | D．no one |
—Can the plane fly _____ the Atlantic Ocean?
—Yes,but it needs to go_____the clouds for hours.
| A．across,through | B．through, across |
| C．across, across | D．through, through |
—Can you tell me _____when the teacher came into the classroom?
—Sorry,I don’t know.
| A．what were the students doing |
| B．what are the students doing |
| C．what the students were doing |
| D．what the students are doing |