——________do you go to the dentist?——Let me see, twice a year, maybe.
Mr.Smith, together with his two sons,_____Shanghai for about five months.
— Air quality in our city is becoming worse and worse. —Yes. These days' PM2.5 readings are frightening. We must do something to ______air pollution.
---Do you like tea or coffee? --- coffee. I prefer coffee ______ milk.
What _____ good time we had________ a picnic yesterday!
—How did you find your visit to Qingdao, Joanna? — _________.