It is our duty to our classroom .
Throwing waste into river will cause problems.
Although I'm my friend, we take things very seriously.
Chinese leave the countryside to search for work in cities.
The modern technology allows us to communicate with people from .
There are pictures of bikes and shapes.
, it's also very important to communicate with them politely.
—We study (在相同的学校), Dongfanghong School.
What are you going to be when you ?
Many teenagers the scientists like Yuan Longping.
Simon, in public places.