He was only a callow youth.

他只是个无经验的年轻人。

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Satan pocketed a bottle and shuffled toward the car. Peeking inside, he saw a callow young man at the wheel. "Where you headed?" he said.

撒旦将一只瓶子揣进口袋，拖着双脚走向车子。往里一瞄，发现驾车的是个愣头小伙子。“你去哪？”他问。

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A callow young toff falls for a beauty of shaky morals and follows her to the end of the world, shedding fortune, scruples and self-respect along the way.

一个乳臭未干的年轻花花公子爱上一个道德成问题的美人并追她到天涯海角，一路散尽家财、抛弃良心和自尊。

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Among my favourite parts of the book is Mr Mehta's early life in London in the swinging sixties as a callow young man, who arrives from India with a few shillings and bags of Indian tea.

BBC: Vinod Mehta memoir a rare and salacious Indian tell-all

As a callow bond-trader, fresh out of college, he participated in one of the greatest of them all, in Japan in 1986, when the yield on the ten-year benchmark Japanese government bond fell to 2.5%, the discount rate at the time.

ECONOMIST: Buttonwood

They're still a bit callow and more savvy than sophisticated, but they gather their own information and have their own notions of what is worthy.

FORBES: Revenge of the Nerds