Opera singers, we're not muscle men; you have to be careful about your work.

You have to be careful to react when you start to deviate from your course.

Be careful what you set your heart upon - for it will surely be yours.

Be careful what you set your heart upon - for it will surely be yours.

So we have to be careful because if you don't protect your culture you won't have it for very long.

You got to be careful of the company you keep.