His misunderstanding of language was the primary cause of his other problems.

他对语言的误解是他其他问题的主要原因。

《柯林斯英汉双解大词典》

But female choice probably is not the primary cause of the traits.

但是，女性的选择或许不是导致这些特征的首要原因。

youdao

But if they do, the company he runs will be the primary cause of it.

如果真的发生了，他所执掌的公司应该是主要原因。

youdao

The U.S.Environmental Protection Agency,or EPA, lists stormwater as the primary cause of water pollution in the United States, and encourages local communities to develop management plans to treat run-off before it pollutes their rivers, lakes or streams.

VOA: standard.2010.08.04

The government blames growth of consumer goods output as a primary cause of inflation.

CENTERFORSECURITYPOLICY: Center for Security Policy | Western Corporations�� ��Short March�� Back To China: Bad Business, Awful Public Relations, Dangerous Policy

"I would say there the primary cause of death was hanging and torture, " his statement said.

BBC: Al-Sweady Inquiry: Iraq teenager was hanged, says uncle

Every day, 2.5 billion people are exposed to the primary cause of death: unsafe water.

UNESCO: Post-Conflict and Post-Disaster Responses