20. There is only one day left for us in Hangzhou and we will have a ________ tour around the city.
If you do not feel well, you should not ____going to see the doctor. ?
The period ____dance classes increases gradually from two or three hours a day to five or six.
Some eighty years ago three-quarters of American production ____family farms or from business employing fewer than six people.
The college is planning to offer more English courses to ____the needs of beginners of English.
The folk song concert was so well ____that all the tickets had been sold out on the first day.