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【简答题】
_______是苹果、草莓、菠萝、香蕉等多种水果的风味物质，它是以_______为前体合成的。
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皮皮学刷刷变学霸
举一反三
【单选题】Mr. Bo _____ for half a month. He’ll come back in two months.
A.
left
B.
leave
C.
has left
D.
has been away
【单选题】— Where’s your brother? — He ________ the library with his friend. He’ll be back in two hours.
A.
goes to
B.
has been to
C.
come from
D.
went to