—Robert is indeed a wise man.—Oh, yes.  How I have regretted ____ __his advice?

The matter _______people’s health surely requires ______ carefully.

The traditional approach ____ with complex problems is to break them down into smaller, more easily managed problems.

The newly-discovered evidence led to the criminal ____ to five years in prison.

It was ______ the second-hand bus that the mechanic spent the whole afternoon in the factory.