How do you say, ''I did do that.''
In English, if you want to emphatically say that something happened, you can say, for example, ''I did do that.'' It may sound silly to a non-native speaker, but we use that construction all the time. ''I did finish my homework.'' It's for emphasis. To just casually say you did your homework: ''I finished my homework.'' If you say, ''I did [do something]'' it is like you are denying something another person said, real or imagined.
Is there a similar construction in Spanish?