Agree to do something 是同意做某事 如：my dad agrees me to buy a new car 我爸爸同意我买辆新车
About to do something 是准备做某事,如：i am about to go to school 我准备去学校了
列子比较简单,但是用法是没错的,我是说解释，不是造句哦，麻烦帮我解释一下，就象解释单词一样，谢谢