初中英语不定式、动名词、序数词等细节问题1、Thegirlhadrunoutofmoney(buy)books是用tobuy还是buying?我总觉得buying对,答案上也是,但是书上课文里是tobuy,请指教2、Lucyis(aninth/thenint

Question

初中英语不定式、动名词、序数词等细节问题
1、The girl had run out of money _____ (buy) books
是用to buy还是buying?我总觉得buying对,答案上也是,但是书上课文里是to buy,请指教
2、Lucy is _____(a ninth/the ninth) grade student who wants to be a professional singer
为什么不用the ninth?不是序数词前加定冠词the么
3、Could you do something for me,please?
_____(With pleasure/My pleasure)两个是不是都可以用?
回答是请详解,说情理由,要有根有据,事成之后定会追加
我要的是根据、理由！
否则别怪我不给分！

Answer 1

1.用to buy,
2.选a ninth："a"这个定冠词其实修饰的是"ninth"后面的"student"
3.两者皆可（我认为）