With the word “PM2. 5” constantly __________ in media reports, you might be wondering what on earth it means.
| A．appeared |
| B．appearing |
| C．to appear |
| D．being appeared |
She ________ her hairstyle in her hometown before she came to Chongqing for a better job.
| A．would change | B．has changed | C．changed | D．was changing |
The crazy fans ________ patiently for two hours and they would wait till the movie star arrived.
| A．were waiting | B．had been waiting | C．had waited | D．would wait |
He kept looking at her, wondering whether he ________ her somewhere.
| A．saw | B．has seen | C．sees | D．had seen |
She has set a new record, that is, the sales of her latest book ________ 50 million.
| A．have reached | B．has reached | C．are reaching | D．had reached |
—You were out when I dropped in at your house.
—Oh, I ________ for a friend from England at the airport.
| A．was waiting | B．had waited | C．am waiting | D．has waited |