问题描述:
1,does he have to practice speaking english every day.为什么speak要加ing?2,我不得不在六点以前到家
i have to get home by 6 o'clock"以前”为什么没有before这个单词?为什么用by不用at?3,we had fun riding our bikes to the beach today为什么rid要加Ing?
i have to get home by 6 o'clock"以前”为什么没有before这个单词?为什么用by不用at?3,we had fun riding our bikes to the beach today为什么rid要加Ing?
问题解答:
我来补答展开全文阅读