They had to be careful of floating chunks of ice.

他们不得不小心漂浮着的厚冰块。

《柯林斯英汉双解大词典》

I had to be careful not to get a sore throat and lose my voice.

我必须小心，不要患上咽喉炎而哑了嗓子。

《柯林斯英汉双解大词典》

The United States has to be careful it doesn't overplay its hand.

美国得注意不要高估自己。

《柯林斯英汉双解大词典》

Companies also have to be careful or they could get into trouble with the Equal Employment Opportunity Commission.

VOA: special.2011.02.28

So it's a way of reminding you, I've got to be careful about the types of things that I put in.

因此我这是在提醒你，一定要对输入的东西的类型,多加注意。

麻省理工公开课 - 计算机科学及编程导论课程节选

The message I'm trying to get to here, because I'm running you right up against time, is I have to be careful about what's a primitive step.

我想说的事情是，因为我正在跟大家讲算法时间复杂度，我们需要注意一个基本步骤的定义,如果我可以假设。

麻省理工公开课 - 计算机科学及编程导论课程节选

At the bottom, Mr Cameron encountered incredibly fine silt, which he had to be careful not to disturb.

BBC: James Cameron back on surface after deepest ocean dive

But she advises investors to be careful because of other disappointments that could hit the company.

FORBES: Magazine Article

But we ought to be careful not to vilify this profession while doing so.

CNN: The courage of teachers