be not able to do sth be unable to do sth区别

be not able to do sth be unable to do sth区别 be able to do sth may not able to do sth 还是 may not be able to do sth? 用be able to do sth造句 英语 翻译 be able to do sth be able to do sth 意思 用法! be able to do sth 等于什么 be unable to do与be not able to do有什么区别 be able to do sth be able to do sth 的同义词是什么? be to do sth和will do sth的区别 I imagine sb.to be able to do sth. be able to do sth 更多用于什么时态?