一只西瓜的果实内有多粒种子,这说明它的雌蕊的结构是[ ]
A.一个子房,一个胚珠
B.一个子房,多个胚珠
C.多个子房,一个胚珠
D.一个子房,没有胚珠
答案:B
—Have you heard from Janet recently?
—No, but I ______ her over Christmas.
A.saw
B.will be seeing
C.have seen
D.have been seeing
因素分析法是最简便但揭示能力最强的评价方法。()