Only in pairs
Step 1: Before you are 3 glasses, 2 of which stand upside down.
Step 2: It is given the task - for 3 turns to put all 3 glasses on their base.
Step 3: Condition: for 1-in turn it is necessary to turn over 2 glasses at the same time. All glasses should be in the correct position only after the third move.
Step 4: Do you want to see how this should be done?
Step 5: The answer is: step one.
Step 6: Answer: step two.
Step 7: Answer: step three.
Step 8: That's all! Now all glasses are right!