John was as bouncy and ebullient as Helen was diffident and reserved.

约翰活泼、热情；而海伦却羞怯、矜持。

《柯林斯英汉双解大词典》

He was modest and diffident about his own success.

他很谦虚，不愿谈及自己的成功。

《牛津词典》

Speak out, my boy--don't be diffident.

说出来吧，孩子——别害怕。

youdao

We on the other hand remain curiously diffident - and rather dishonest - on the subject.

BBC: UK

So Beane hires as his assistant a pudgy, diffident non-athlete named Peter Brand (Jonah Hill), an economics major a few years out of Yale, who happens to be a disciple of the sabermetrics guru Bill James.

NEWYORKER: Playing The Numbers

He co-stars as Colin, a diffident aspiring writer whose older sister, J.

NEWYORKER: The Color Wheel