--- Has he returned the book to our library?
--- No. He has _______ it for several months.
要运40袋尿素和60袋复合肥，选择载重量为几吨的卡车比较合适？
①商业活动突破空间限制 ②城市商业活动比较繁荣
③政府开始鼓励商业发展 ④商品分区排列和出售
下列关于农业带的划分的说法，正确的是（ ）
