After the meeting, she invited us to dinner at her home and treated us _____ many exotic foods we _____ before. It was really a wonderful treat.
| A．with; had never tasted | B．to; have never tasted |
| C．with; have never tasted | D．to; had never tasted |
With the word “ PM2.5” _________ appearing in media reports, people pay greater attention to it and seek health tips for smoggy days.
| A．constantly | B．consequently | C．permanently | D．immediately |
Hiking is _____ great fun. You will get close to ____ nature and take exercise at the same time.
| A．a; the | B．a; 不填 | C．不填；the | D．不填；不填 |
I couldn't imagine ______difficult it was for these badly injured victims to make it to the hospital.
| A． when | B．how | C．what | D．where |
—Where did you get this book?
—I picked it up from a second-hand bookshop if you ______know.
| A． must | B．will | C．can | D．shall |
—What are you two whispering about over there?
—Oh, ______. Just small talk.
| A．no | B．nobody | C．none | D．nothing |