【判断题】插穗的年龄与插穗的分生能力,切口愈合生根有密切关系,一般以1年生枝最好。
【单选题】He was admitted to our school two years ago, a top school in our hometown, _____ he has been crazy about reading electronic novels, killing time.
【单选题】尼龙是世界上最早实现工业化生产的合成纤维,它的发明使纺织品的面貌焕然一新,被称为该表世界的重大发明之一。下列选项中,尼龙的发明人是()
【单选题】Our school has fifty ____teachers.
【判断题】对于光敏电阻的恒流电路,其输出信号取决于光敏电阻和负载电阻的比值,与偏置电压成反比
【判断题】光敏电阻在恒压偏置电路比恒流偏置电路的电压灵敏度要高一些。
【单选题】Our school has a big basketball__________and asoccerfield.