He said he agreed but his voice lacked conviction.

他说他赞同，但语气不坚定。

《牛津词典》

But his voice kept vanishing.

但他的声音在不断消失。

youdao

His gait was halting, but his voice was strong.

他步态蹒跚，但声音坚定。

youdao

So they were silent. Oh,well, said the captain, Well get ashore all right. But there was something in his voice that made them think, as the sailor said: Yes,if this wind holds! Seagulls flew near and far.

VOA: special.2010.03.06

(Voice) But Kumar is determined to give a good education to his three-year-old son, so that when he grows up, he can live in a bigger house, and afford a car.

VOA: standard.2009.11.27

But his voice is not an obvious match to that of the mysterious al Qaeda envoy.

CNN: Mysterious al Qaeda 'envoy' dispenses aid in Somalia

In this version, Mr Pop may look like he's consumed the contents of several pharmaceutical cabinets, but his voice, when it comes, is extraordinary.

ECONOMIST: Business travel

He remains incredibly thin, but his voice was strong.

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