45The twins look much like each other, but they are different _____ nature

Since David ________ downloaded a virus into his computer，he can not open the file now[ ]

Scientists suggested parents _______ children do the housework to make money.

_______ can a tiger weigh, do you know —Yes, I know that a big one can weigh over 300 kilos.

Time for bed, Dear. — Not yet, Mum. I _____ until I _____ going over my lessons.