－I looked after a group of fifteen French children, you know.
－That easy
| A．mustn’t be | B．mustn’t have been |
| C．can’t have been | D．can’t be |
— Do you know __________ they got to know each other?
— It was last year ________ they both taught English in China.
| A．when was it that; when | B．when it was that; that |
| C．when it was that; when | D．when was it that; that |
— It’s no easy task to catch a ticket on a website that receives 1 billion clicks daily.
—I can’t agree with you more. There ________ be errors for every single step.
| A．should | B．must | C．will | D．can |
—I wonder what makes you a successful manager.
—I ________ as a waiter for five years，which contributes a lot to my today’s work.
| A．serve | B．have served | C．had served | D．served |
----What’s that noise?
---- There’s a truck stopping outside．It’s someone something.
| A．deliver | B．to deliver | C．delivering | D．delivered |
After the trainer was sure that the whale could look after itself, he _______ it into the sea.
| A．transported | B．delivered | C．released | D．handled |