Yes, dreams are composed of images. At times it feels like we are "looking" something we have never seen when what's happening is that our brain pull random data to create the most fascinating images

I think you are asking if a person had no language skills could s/he dream. If so, yes because a dream can be made of any type of images And may contain no words. And now that I am saying that it makes me wonder what a blind person's dream would look like, especially someone blind since birth. Any ideas on that?

My dreams have been very vivid lately and I remember them clearly. They are in color and with dialog. Conversations are usually between people who I've known and myself, but sometimes there is a talking chicken, cat or goat in there helping out with instructions. Not too bizarre. Sometimes the setting is surrealistic big buildings and other times it is just open countryside with small farm homes. Last night's dream was in a stranger's house where I was asked by a very small girl to help her calm down her mother. Her mother came into the room screaming obscenities and I walked over and hugged her. It worked. Then I woke up.

Good question. As when you are awake, the ability to comprehend things is directly related to the language we speak. As we grow, and our language advances, so does our ability to see inside our heads. Any one fossilized group of pictures in the mind is understandable without language but language is needed to subconsciously relate 2 or more groups of pictures within. So yes but limited to only 1 picture group with no complexity or reason to remember upon waking.

This could turn into a legthy conversation about the acquisition of language, social cognitive inference, and nonverbal communication. Simply put, yes the animal kingdom dreams. And yes only homo sapiens have a symbolic representation of their consciousness that can be expressed in a written form of tonal inflections and cognates.

Can a human exist into adulthood without language? Probably not. If there are other people to communicate with language as such a huge part of the human experience that there would almost certainly be a form of language even if not taught a language.
So to answer the question, yes because language isn't required for dreaming but it is a moot point. Language would be part of everyone's dreams at least part of the time. It doesn't have to look like typical interpretation of language though.

Yes.

Did you know that as far as we can tell, humans mostly dreamed in color until the invention of the television... Most people who grew up with a black and white television had dreams in black and white and it switched back to color for those who grew up with color televisions. Trippy shit. As far as language goes... I'd assume so.

mine rarely involve words, so no language for me.

most of my dreams are just imagery

I always dream and not hear or say anything. When its a talking dream ...i talk out loud.

Yes.

Let there be the entities "can", "a", ..."?". , in such that every aspect of this question exists.

If there exists a "cannot" in stead of a "can", then a human cannot dream without a language, in which case we are out of the space in question, which is absolutely no space at all.

So inevitably, any means of thinking about this question ultimately leads to otherwise.

Therefore, a human can dream without a language.

Yeah, if cats & dogs can do it, I imagine we can too.