The severe flooding \_\_\_\_ if the authorities had cleared the drainage systems and taken proper precautions ahead of the heavy rainfall.
Aought to be avoided
Bmust have avoided
Cwill be avoided
Dcould have been avoided正確答案
答案與詳解
為什麼答案是 D
could have been avoided 符合第三類條件句主要子句的句型（could + have + p.p.），且使用被動語態（been avoided）正確表達「水災本來可以被避免」的語意。
載入中…
