He philosophized, he admitted, not because he was certain of establishing the truth, but because it gave him pleasure.

他承认自己反复推究不是因为他确定找到了真理，而是因为那给了他很多乐趣。

《柯林斯英汉双解大词典》

This task was meant to be similar to learning about animal species in a biology lesson. It used aliens in place of actual species to be certain that the participants could not draw on prior knowledge.

这项任务旨在模拟生物课上学习动物种类的过程，它之所以用外星生物代替实际物种，是为了确保测试者不会凭借其原有的知识进行记忆。

youdao

Most of them were certain that it was not my own composition.

大多数同学说这首诗绝不是我自己写的。

youdao

He said he was also worried that it was not yet certain if an inspector would stay in the south of the county to oversee operations throughout his constituency.

BBC: Ludlow MP fears 999 response teams may go

Professor Michael Shaw, a plant health expert at the University of Reading, who was not involved in the research, said it was a step towards understanding why certain strains of the fungus cause disease while others are benign.

BBC: Ash fungus genetic data released

This circumstance was pretty unique in that Secretary Bryson was alone, was not with a security detail, was on private time, which is common for certain members of the Cabinet, and it resulted in him being -- both having a seizure and ending up in the hospital.

WHITEHOUSE: Press Briefing