英语语法填空有一题
问题描述：
英语语法填空有一题
Mom is in her seventies,and those hands I once_____(think)to be so rough are stil doing things for me and my family.
为什么不能用have thought 而一定要用thought.
答
关键是前面有once（曾经）,这是表示过去时间的词.现在完成时不能和表示过去的时间状语连用.因为现在完成时属于“现在”的时态范畴.
顺便说一下,I once thought to be so rough是定语从句,修饰those hands.