質問: Found this in a book where a student was being scolded for playing a prank on the teacher with his car. The teacher was panting so the dialogue was broken up. Not sure if that's why I'm confused. > > それは... > 君が毎日... > 私としてた > からでしょ > > > もう私... > 少しの > ガソリン消費で > > > The "私としてたからでしょ" confuses me the most here. I've learned of として when it means "in the role of". Is that what it means here? Is it different from this definition here? If any more context helps, the student used his teacher's car and used up all the gas.
回答: This usage is not related to the Xとして. してた is alternative/colloquial way of saying していた, a past form of している (from する). And と here is simple “and/with”. So 私としてた is “[you] were doing with me”.