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be careful of is the most popular phrase on the web.

be careful for 11,220,000 results on the web	be careful of 17,830,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Intellectual property is important, but we have to be careful for this initiative not to overlap common initiatives, joint undertakings. Our appeal is great, young friends, but be careful for the city's light casts many shadows. I do have to be careful for her fire. You better be careful for a while. You better be careful for a while. I have to be careful for a speeding ticket The season wasn't the same as in the other sequences so we had to be careful for the link shots since the vegetation was slightly different. since I must be careful for the sake of the child and not let him enjoy his conjugal rights.	Yes, but be careful of her head. I have to be careful of heart strain and muscle fatigue. I didn't mention that you were ill, so be careful of what you say later. What we must be careful of in the field of taxation is not taking into account the needs of certain Member States. You have to be careful of the woman who has no underwear. Lizzy... be careful of your husband. I told you when this began to be careful of those people. You want to be careful of that thing, you know.

be careful for

11,220,000 results on the web

be careful of

17,830,000 results on the web

More popular!

Intellectual property is important, but we have to be careful for this initiative not to overlap common initiatives, joint undertakings.
Our appeal is great, young friends, but be careful for the city's light casts many shadows.
I do have to be careful for her fire.
You better be careful for a while.
You better be careful for a while.
I have to be careful for a speeding ticket
The season wasn't the same as in the other sequences so we had to be careful for the link shots since the vegetation was slightly different.
since I must be careful for the sake of the child and not let him enjoy his conjugal rights.

Yes, but be careful of her head.
I have to be careful of heart strain and muscle fatigue.
I didn't mention that you were ill, so be careful of what you say later.
What we must be careful of in the field of taxation is not taking into account the needs of certain Member States.
You have to be careful of the woman who has no underwear.
Lizzy... be careful of your husband.
I told you when this began to be careful of those people.
You want to be careful of that thing, you know.