21.--- This kind of cloth ____ well and____ long, besides, it’s cheap.--- OK, I’ll take it.
—Is the experiment easy?— ________ . I'll just do my bit.
Although he knew little about the large amount of work done in the field, he succeeded ________ other more well - informed experimenters failed.
—Where have you been recently? —I ________ in Hangzhou on business for a week last month.
The big- eyed girl came in, ________ a cake with two ________ candles on it.
Before Tom left home, his mother kept telling him to ________ his manners at the party.