A low-carbon(低碳) lifestyle has an effect our daily life. People are paying more and more attention to energies these days.
---How many students have visited the West Lake? ---________.
When I was in the USA,I had difficulty ______ English, so I often ask Paul ____ help.
The river is too wide for the swimmers _______________.
I don’t know ______ with this problem. It’s too hard.
The notebook ___________ be John's .There is his name on it.