They are seriously concerned about security.

他们非常关注安全问题。

《牛津词典》

He was very seriously concerned with the problems involved.

他非常关心与此相关的问题。

youdao

Yesterday, Russian news agencies cited an unnamed Russian official as saying Moscow was "seriously concerned" by Iran's latest declaration.

昨日，俄罗斯新闻机构援引一位未具名的俄罗斯官员的话称，莫斯科“严重关切”伊朗方面的最新声明。

youdao

"We are also seriously concerned with the recommendations that these allegations be taken up by the Security Council and then possibly referred to the International Criminal Court."

VOA: standard.2009.09.29

"They would be seriously concerned that there would be a job loss announcement, " he said.

BBC: Seagate

If Dr. Bernanke were paying attention to the numbers, he would be seriously concerned right now.

FORBES: QE Part III, Peanuts Edition: Ben Bernanke As Lucy Van Pelt

Its authors said they were "seriously concerned about the effect on patient management and safety".

BBC: Stafford Hospital breast cancer services criticised