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be careful

To act cautiously. Usually issued as a warning. Be careful when you go out in the city at night. Be careful with that box—don't bang around my glassware! Be careful! Stay with the tour guide!
See also: careful

be careful not to (do something)

Proceed cautiously, in an attempt to avoid potential problems or pitfalls. This phrase is often said as a warning or instruction. I was careful not to make any noise as I crept into the house after curfew. As you plan your talk, be careful not to bore the audience with scientific terms they won't understand. This plate is very hot—be careful not to burn yourself.
See also: careful, not

you can't be too careful

One must exercise the utmost caution and prudence (in the face of a very dangerous, risky, or problematic thing or situation). I'm sure everything is in order, but I'd like to have my lawyer read over the contract one more time—you can't be too careful. I think you should wear one of those holsters that keeps your passport and some extra cash hidden under your clothes. You can't be too careful when you're traveling abroad alone, you know.
See also: careful

Be careful

1. an instruction to take care in a particular situation. Bill: I'm going to the beach tomorrow. Sally: Be careful. Use lots of sunscreen! Jane: Well, we're off to the Amazon. Mary: Heavens! Be careful!
2. a way of saying good-bye while cautioning someone to take care. John: See you around, Fred. Fred: Be careful. Alice: Well, I'm off. John: Bye, Alice, be careful.
See also: careful

careful not to do something

using care to avoid some difficulty or difficulties. Please be careful not to discuss politics with Mr. Brown. Please be careful not to leave the house unlocked.
See also: careful, not

careful (with something)

treating or handling something with caution. Please be careful with the vase. It's old and valuable. That's too big a load. Be careful!

If you can't be good, be careful.

Prov. If you are going to do immoral things, make sure they are not dangerous.; If you are going to do something immoral, make sure to keep it secret. (Sometimes used as a flippant way of saying good-bye.) Be a good girl on your vacation trip. Or if you can't be good, be careful. Ernest likes to close his letters with, "If you can't be good, be careful."
See also: careful, if

you can’t be too ˈcareful

used to warn somebody that they should be careful to avoid danger or problems: Don’t stay out in the sun for too long — you can’t be too careful.
See also: careful
References in periodicals archive ?
Inspired by Jose Mari Chan's pop ditty "Please be Careful with My Heart," the series shot to No.
Read the signs follow the diversions CONCERNED RESIDENT AND CAREFUL DRIVER Lamb Hall Road
Co-authored by sisters Joan Dickow and Judy Snider, the idea of I Love You, Be Careful started from a telephone conversation one day when the sisters talked about wanting their loved ones to be safe and know how much they are loved.
The bank said that it would be more careful on what businesses in would focus on following regulatory requirements changes.
We would advise people to be very careful when out and about and to stay warm.
The CEO of Germany-based Deutsche Bank (NYSE: DB) has called for careful global bank regulation.
3 : careful thinking about something so as to be able to take action on it <This matter requires immediate attention.
Democrats are more careful to recycle glass (18 percent) than Republicans (10 percent), and Republicans are more careful to recycle plastic (24 percent) than Democrats (16 percent).
But, Robertson's careful attention to the court records and the New York SPCC files reveals not only how frequent and varied these crimes were, but that the success of this initial campaign, in New York at least, was actually quite limited because juries, drawn from ordinary citizens, and even judges rarely approached the law in the categorical ways that reformers hoped to institutionalize through the passage of new laws.
Kuma has been careful to emphasise the multi-purpose aspect of the museum: 'It still is a house, even though it's located inside an art museum.
We have a very positive vision of SQM because it is taking advantage of good prices for its main products and being very careful bringing on new capacity," says Errandonea.
Careful surveying and photographic documentation in conjunction with current CAD drawing technology allowed effective planning and coordination, resulting in successful completion of the work without disruption to the ongoing activities of the hospital.
She can be approached barehanded, though, if you are careful to grasp her firmly, smoothing down the hairs away from the stalk at the center of the plant, rather than brushing the hairs the "wrong way," against the leaves toward the central stem.
Be especially careful when driving on wet, slippery roads.
Read the story below, paying careful attention to the words and phrases that appear in boldface.