Dongdong is six and he is in Grade One. His sister Jill is ten and she is in Grade Four. Now they are going to buy some vegetables.

    On the road, Jill asks, "What's two times seven?" "Sorry, I don't know." "Come with me and I'll show you." Jill says at the shop. They buy seven kilos of potatoes and the potatoes are two yuan a kilo. So they're 14 yuan in all. And then they go out of the shop. Dongdong says, "I know two times seven is fourteen." "Yes, you're so clever." Jill says.

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