ambition是什么意思？

They resonated(共鸣) with optimism and ambition in much the same way as the most famous dream speech of all, delivered by Martin Luther King Jr.

They can only be solved by people with optimism and ambition

Behind the differences in sex, skin tones and mother tongues, there are common attitudes, expectations and ambitions which risk creating a set of clones among the business leaders of the future.