你的理解是对的.
比如说：
He (learn) English since he was 4.
He has learnt English since he was 4.
根据所给语词适当形式填空我对这题目意思不懂,是只用所给单词的变换形式填空?能不能在加上一些时态必须词语
你的理解是对的.
比如说：
He (learn) English since he was 4.
He has learnt English since he was 4.