The fact the plane has not appeared on radar when it neared land gives me cause for concern.

这架飞机在接近着陆时没有出现在雷达上的事实让我感到担忧。

youdao

There is no cause for concern.

没有理由担忧。

《牛津词典》

As far as we knew, there was no cause for concern.

就我们所知，没有什么要担心的。

《牛津词典》

With this latest discovery, the researchers say noise pollution in coral environments raises yet another cause for concern for these organisms.

VOA: special.2010.08.10

So, if I wanted to cause you to feel moral concern for a fetus, I would do well to describe it as a pre-born child.

所以如果我想你对胎儿产生道德关怀，我最好就称它为未出生的婴儿。

耶鲁公开课 - 心理学导论课程节选

Although that might cause concern for some people, forcing people to vote is definitely not the answer.

也许这会让一些人担忧，但是强迫人们去投票绝对不是解决问题的方法。

对于义务投票制 - SpeakingMax英语口语达人

While net income was above consensus estimates, both sales and margins were a cause for concern.

FORBES: Is Apple The World's Best Value Stock?

If the centre were better at raising revenues, there would be little cause for concern.

ECONOMIST: China

The US said it was aware of the move, but did not see cause for concern.

BBC: Envoy Kofi Annan presses Iran and Iraq over Syria crisis