—Are you free tomorrow afternoon?
—I'm afraid not. I'll have to __________ an important lecture given by a famous professor.
| A．join | B．take part in |
| C．attend | D．enter |
He failed in the exams and only then _____ how much time he had wasted.
| A．he realized | B．did he realize | C．he had realized | D．had he realized |
This ticket _____ one adult and one child to the show.
| A．promises | B．enters | C．admits | D．includes |
— Isn’t it hard to drive downtown to work?
—Yeah, that’s why I ______ to work by train.
| A．have gone | B．have been going | C．was going | D．will have gone |
— Shall we go and have a picnic at the weekend?
— ______. According to the weather forecast, there might be a cold front by then．
| A．Why not | B．We can wait | C．No, let's not | D．It depends |
She is _____ newcomer to _____chemistry but she has already made some important discoveries.
| A．the; the | B．the; / | C．a; / | D．a; the |