初二英语、用括号中单词的正确形式填空.

问题描述:

初二英语、用括号中单词的正确形式填空.
如题
she made a living by _____(sew) for others.

答案:sewing
介词by 后跟动名词- 动词ing形式
不明白的再问哟,请及时采纳,多谢!还有一题哦、、 the students in 12th grade are called (senior) in the USA.括号里的那个单词要不要用复数形式?本句子时复数,所以名词也用复数 seniors客气