1. I'm debating between... [option A and option B] 2. I can't make up my mind. 3. I'm on the fence. (= I'm in the middle, I don't know what to decide) 4. I'll take that into consideration. 5. On the other hand... 6. I'm having second thoughts. (= I'm reconsidering my decision) 7. I changed my mind. 8. He convinced/persuaded me to... 9. Looking back, I know it was the right decision. 10. It's up to you. (= You can decide)
It is easy to spot a teacher who loves their work. They seem to emanate contagious energy. Even if it on a subject like advanced calculus, the subject comes alive. If you dont love your work or your subject, it will come through in your teaching. Try to figure out why you feel so unmotivated and uninspired. It might have nothing to do with the subject, but your expectations. Adjust them a bit and you might find your love of teaching come flooding back.