题目内容：

Many trees__on each side of the street every years.A are plented Bare planting Cplant

优质解答

答案：A are plented
翻译：每年许多的树都被种在街道的两边.
这里很明显,树做主语,应该用被动语态,
主语为trees复数形式,因此谓语动词用are plented.