Supposing you said "A", it doesn't mean that you were meaning to say "A". Contexts are important, too. Perhaps you said "A" because you wanted to say "B". Or because you were raised to talk about something in a roundabout kind of way. Backgrounds also matter. Some culture prefers to be blunt, some habits (from our environment, parents, etc.) nudge us to evade the issue and expect others will be able to read between the lines.
When I said "cats" for instance, what would you think? You might think that I was referring to cats in general. Or perhaps I was complaining about my (I like to think that they are) domesticated cats. One can't be too sure.
The hard thing is, when you say something, you expect people will understand what you are saying. You hope people would guess what really bother you and perhaps talk about it.
Some miscommunications are bound to occur.
I don't like small talks. Whenever I ask, "How are you?" I always mean it. I always want to know what that person really feels. Even if (s)he is feeling lousy, is sick, or anything, I really want to know the details. Now, it took me a while to realize that to some, "how are you" is just... well, small chit-chat. You are expected to answer, "I am fine!" even though that time you are bleeding in the middle of a lonely road after being stabbed repeatedly by an unknown assailant, and you know, you just know, that you are dying. My imagination is gruesome? Ah, that is true, and I am now digressing.
The key is gauging what others are really saying. Reading between the lines. If a person says A, does he really mean A, or perhaps he hints of B? Think. Observe. Remember his or her background, try to understand the circumstances.
And most importantly, guess. Because, you really can't tell, can you? You just guess, and hope that you're hitting the mark.
Or at least, close to it.