1. Keep up the good work! 2. That was a nice try. (say this after someone made a good effort but failed) 3. That's a real improvement. 4. You're on the right track. 5. You've almost got it. 6. You're doing great. 7. Don't give up! / Hang in there! (when someone is currently having difficulties) 8. You can do it! 9. Give it your best shot. (best shot = best try, best effort) 10. Nice job! / You did great! (after the person has done something good)
The most obvious and famous drawback to induction cooking has already been mentioned: it only works with cooking vessels made of magnetic materials. The commonest such materials used for cooking vessels are stainless steel and cast iron. Cookware suited for use with induction cookers, from the extreme high quality end down to thrift store modest, is readily available; but if you already have a stock of mostly expensive aluminum or copper or glass or pyrex cookware and little or no cast iron or stainless, you might be up for a cookware investment.