______ the red switch on the left and the flying machine will swiftly go up into the air and _____ its journey.
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Let's go a little faster, ______________ we'll never get there on time.
| A．yet | B．or | C．so | D．and |
.
—How long have you been here?
—Only about five minutes. Henry and Simon _____________ here with me.
| A．walk | B．have walked | C．walked | D．had walked |
.
—Was _________________ problem solved?
—We were trying to think of _________________ way out, but it was difficult to find one.
| A．a; a | B．a; the | C．the; a | D．the; the |
.
Take the spare batteries with you _________________ you need them.
| A．so that | B．even if | C．as long as | D．in case |
.
—Which T-shirt do you prefer? Blue or green?
— _________________ will be OK. I don’t mind.
| A．Either | B．Neither | C．None | D．Each |