Question

she is singing改为否定句、一般疑问句、对singing进行提问？

Answer 1

否定句：She isn't singing.
方法：直接在is后面加not。
一般疑问句：Is she singing?
方法：is提到句首。
对singing提问：What is she doing?
方法：singing表示正在做的事情，提问用what doing,可当作固定搭配来记忆。

Answer 2

否定句直接在be动词后加上not即可，所以应该是She isn't singing.
一般疑问句则把be动词提前，其他保持不变，所以应该是
Is she singing?

特殊疑问句需要用到特殊疑问词，对singing提问，要用what，后面紧跟一般疑问句，所以应该是What is she doing?

Answer 3

改为否定句为：She is not singsing.
改为一般疑问句为：Is she singsing?
对singing提问为：What is she doing?

Answer 4

否定句：She isn't singing
一般疑问句:Is she singing?
特殊疑问句：What is she doing?

Answer 5

改成否定句是：She isn't singing，
改成一般疑问句是：Is she singing？
对singing进行提问是：What is she doing？