Technically correct, albeit a tad awkward in English.
He is a little and old man = "O küçük ve yaşlı (bir) adam."
The main reason "ve" is added here is to avoid ambiguity I think. "küçük yaşlı" can mean "being of a young age, underaged". Putting the "ve" in clarifies that it's two separate adjectives. That's why they prefer the translation "little old man."
This could also be translated as a sentence in English. It could be "He is the small, old man" :)
Some periods were added in places where they shouldn't have been in the course and we cannot update these (somewhat disappointingly). They will all be fixed in a future version of the tree.
O = he, she, that, Onlar = they Bu = this Şu = that (rarely used instead of "o" for something not being interacted with within arms length of listener) Bunlar = These, Şunlar = Those
Also can look up "demonstrative pronouns" or other curious questions as there's usually a few exceptions and imperfections in any system or language.
Probably because the verb "to be" or VAR (is) missing...as well there is no HE or SHE in Turkish, only they, that, which are always bigender unless if the word man, woman, male, female, boy, girl, is used to indicate...altho I'm not fluent, but Azeri Turkish was one of my mother tongues before learning English replaced my Turkish..
I dont know the complicated version about reflexive vs demonstrative pronouns and technical terms that describe parts of language speech. But I think O & Onlar probably refer to PEOPLE, while Bu, Su, Bunlar, Sunlar maybe refer to objects. Therefore O is "THAT" (, IT, HE, or SHE) for referring to PEOPLE or living creatures, while ŞU is probably "THAT" (or "IT") for objects. Perhaps BU is also THIS or IT for objects. Have fun on your learning and take care.
..hi.. that's cuz (because) in English, saying "AND" ("ve" in Turkçe) sounds abnormal when there are two back to back adjectives (describing words). Ie. That small and old man....vs. That small, old man. Also I just noticed, you can also think of OLD MAN as the noun (person/place/thing) therefore again also negating(reducing) the need for "AND". Good luck and be well!