1.   Sir Brian is loud-mouthing Sir Bernard, who is assaulting the other five with caustic wit.

2.   Some of his students were alienated by his caustic wit.

3.   He turns an often caustic wit on his life, chuckling at adolescent angst from the perspective of midlife.

4.   His abstract paintings and collages seemed to mirror an innate elegance, but he also had a caustic wit and could be outspoken when the occasion warranted.

5.   His caustic wit is one of the reasons for his fame.