Translation:I saw your child.
I'm not fluent so maybe someone else can weigh in too. 看 means to look at or watch something and is a continuous action like 看电影 or 看书. 见 means to meet like 我们见到 (we met). When you put them together, 看见 means you saw it but you dont see it anymore. 见 is a modifier here and tells you the action is not ongoing.
I'm also a beginner so I might be wrong, but as I understand it, 看 is "watch", and 看见 is "see".
That is to say just 看 signals intent or directed attention (like you're watching a film) and 看见 is more accidental. Like the difference between "listen to" and "hear" in english.
I agree. And so many sentences in Duolingo are creepy, I really wonder what kind of "cockroaches" are living in the head (it's a Russian expression) of the people who designed the lessons: I touch the boy, I pay the boy (er, for doing what ???) and a dozen more that are way too creepy to say out loud if anyone is within hearing distance (good thing there's the "I can't talk now" button). At least those were in the Greek tree which I completed, but there are very little differences from one tree to the other. So I assume I'll soon learn to be creepy in Chinese too thanks to Duolingo.
I wonder too. Would it be something like watch and see ? As someone said. Then would i use "kan ni de haizi" in the context of a show where i watched them with intention ? And "jian" would be "i met them"? And "kan jian le" would be "i have seen them over there" ? For the last one i dont mean "a place" but just "see with no intention of looking at them".
wǒ kàn jiàn le nǐ de háizi
我 = "I"
看 = [verb] "(to) look"
见 = result complement of the verb 看. Makes it a compound verb "to see". https://resources.allsetlearning.com/chinese/grammar/Result_complement
了 = following a verb it indicates a completed action. In this sentence it makes the verb past tense (see -> saw)
你 = "you"
的 = possessive particle (you -> your)
孩子 = "child"
In this case it indicates that the action is not currently happening. That is usually how it functions when appearing directly after a verb such as 看见. Typically, any time you want to be clear that something happened in the past, you will use 了 or 过 after the verb, though neither necessitates past tense. If anyone else has thoughts, feel free to correct me.
Not that it is important, but as an American English speaker, maybe I can shed some light on why Duo wanted "saw" rather than "have seen." To me, "I have seen your child," sounds like you mean the same thing as, "I have seen your child before." "I saw your child," sounds more like you are talking about a specific time/place/event where you noticed my child. For instance, "I saw your child at school," would mean that the last time you were at the school you saw my child. "I have seen your child at school," would mean that you, at any ambiguous point in the past, have seen my child at school before. Additionally, I would say, "I saw your child yesterday," but never, "I have seen your child yesterday." In any case, this is all just pointless explanation. I'm not super sure on the British English rules with "saw" versus "have seen," but hopefully that shed some light on the situation.