生长在主茎或枝条顶端的芽称为顶芽；生长在枝条侧面叶腋内的芽称为腋芽或侧芽。
参考答案：对
两个数相加或相乘或相除，交换它们的位置得数不变．______．
Very few people have to finish the work before going home, _________ ?
A．have they
B．do they
C．don’t they
D．haven’t they
