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Q1) "Do" before a verb can play a role of emphasis, can't it?

A: You didn't do your homework again, did you!?
B: Yes! I did do my homework this time.

Q) Is it the natural dialog?
I intended to use "did" as emphasis. (not just simply say, "I did my homework".)

Q2) I found how I can form a negative versioin of it.

A: Did you do your homework?
B: I didn't.
A: What? you did your homework?
B: No!, I didn't do my homework.

Q3) Does "didn't" automatically the same emphasizing form as "did" in the first dialog? (I don't think I should use didn't twice like: No!, I didn't didn't do my homework.
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Q1) "Do" before a verb can play a role of emphasis, can't it?-- Yes.
A: You didn't do your homework again, did you!?
B: Yes! I did do my homework this time.
Q) Is it the natural dialog?-- Yes
I intended to use "did" as emphasis. (not just simply say, "I did my homework".-- Right.)

Q2) I found how I can form a negative version of it.
A: Did you do your homework?
B: I didn't.
A: What? you did your homework?
B: No!, I didn't do my homework.
Q3) Does "didn't" automatically the same emphasizing form as "did" in the first dialog?-- Yes. Negatives by nature are somewhat emphatic. (I don't think I should use didn't twice like: No!, I didn't didn't do my homework.- You're right, you cannot do that.)
Comments  
Can we use this emphasis for other subject like She He It You We They. Ex: She does sew a new dress? Thank you!