Well-behaved: he always ...

Well-behaved: he always speaks as if his mother might be listening.
Well-behaved: he always speaks as if his mother might be listening.

Quotes from the same author

Hatred of the mother is familiar, but the mother's hatred still comes as a surprise.
Staid middle age loves the hurricane passions of opera.
You know you're in love when you stop comparing.
Great men wait for the right moment to abandon caution. The rest of us abandon it when impatience becomes too much for us.
Boredom, not the will, is the mother of change. Necessity is the father.