--Are you satisfied with the air today? --Not at all, it’s so foggy that I often get a cough. I think we all need much ________air to breathe.
The student is afraid _________ English with foreigners.
He would rather ________for himself than________for a meal.
It’s important_______us_______ to our teachers carefully in class.
It’s generous_____ him to donate_____ money to UNICEF.
Do you mind_________?