It's all about context and collocations (how words work together).
You "pay attention to someone or something" (prestar atenção)
, like when you are listening to someone: "You need to pay
to the teacher when he's talking."
You "use caution" (ir com cuidado
). This is quite formal, and I don't think I'd use it when speaking. "Use
while scuba diving. Your life depends on it!"
"Look out" (cuidado
!) is what you yell to someone who is about to either walk off a cliff, get hit in the head by a flying object, or whenever the person needs to pay more attention to what is going on around him. You could also say "watch out!".
You "look out for someone or something" in the same sense as "pay attention" and "use caution" at the same time: "Look out for
bears when you go camping this week."
Now pay attention to all my other posts and use extreme caution when critiquing them!