What shouldn’t sixteen-year-olds be allowed to do?
---How do you learn English? ---I learn watching English videos.
---Did you get there by ______ bike?---No, I took ______ taxi.
—Would you like to go out for a walk with us? — ,but I must finish my homework first.
I usually sleep with the window open _____ it’s very cold.
We have to _________our school trip till next week because of the heavy rain.