植物扦插繁殖时，需要去除成熟叶片、保留芽和幼叶，这样可以促进

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问题选择题

植物扦插繁殖时，需要去除成熟叶片、保留芽和幼叶，这样可以促进插枝成活。其原因是

①芽和幼叶生长迅速，容易成活 ②芽和幼叶储存有较多营养物质 ③芽和幼叶能产生生长素，促进生根 ④去除成熟叶片可降低蒸腾作用[ ]

A．①②

B．③④

C．①④

D．②③

答案

答案：B

选择题

(2013·高考福建卷)The girl has a great interest in sport and ________ badminton classes twice a week over the last three years.

A．took

B．is taking

C．takes

D．has been taking

选择题

Compared with male graduates, a(n) ________ small number of female graduates can get employed when they go jobhunting.

A．casually

B．relatively

C．roughly

D．gradually