How many trees _____ in the last two years Awere pianted Bplanted Chave planted Dhavebeen planted
问题描述：
How many trees _____ in the last two years Awere pianted Bplanted Chave planted Dhavebeen planted
答
D have been planted
句子有时间状语in the last two years,是用完成时态的标志,另外trees是被种的,用被动语态.