What languages have the least amount of "you just have to memorize it"? (Noun gender,verb forms,plurals, etc.)

[lavengro]

lucky winner chicken dinner: Toki Pona. 125 (root) words, no conjugation or declension (regular or irregular), only five words to memorize for the entire range of colours, only three words for numbers.

[Querneus]

Hah, Japanese. No gender, no plurals, verbs are very regular. There are other aspects of this that are difficult, but forming correct simple sentences is simple.

I have to disagree . While regular, verb conjugation is still pretty extensive. A lot of grammar points are not easy to put within some system, but just something to be memorized. Politeness level affects not only verb conjugation but the choice of word (a proper synonym). There no "normal" adjectives one could easily map to Indo-European grammar. Those are either defective verbs (and can be conjugated) or Chinese-style two-three-four kanji-combinations which can be used kinda like adjective but not really as such. And often as nouns as well. There are also tari-adjectives, which you just have to memorize. Numerous personal pronouns (well, actually they are not really pronouns )

Vocabulary is very different, you just have to memorize it. On the top of it, there is a kajillion of kanji. You just have to memorize all of them .

There is a lot, lot, lot of memory work involved while studying Japanese.

You forgot to mention the fact you have to memorize at least one classifier (or "measure word") for each noun, which is especially pertinent to this thread.

[Ezra]

You forgot to mention the fact you have to memorize at least one classifier (or "measure word") for each noun, which is especially pertinent to this thread.

Indeed.

I should have probably mention that unlike in Chinese, Japanese kanji have highly irregular reading, and one kanji might have up to dozen(s) of readings. It is like in English but much, much worse. It is possible to make a guess, but at the end of the day you just have to memorize how to pronounce a word.

[rdearman]

Esperanto. This was one of the goals for which it was created.

lucky winner chicken dinner: Toki Pona. 125 (root) words, no conjugation or declension (regular or irregular), only five words to memorize for the entire range of colours, only three words for numbers.

The OP specifically excluded ConLangs, constructed languages.

[Cavesa]

Esperanto. This was one of the goals for which it was created.

lucky winner chicken dinner: Toki Pona. 125 (root) words, no conjugation or declension (regular or irregular), only five words to memorize for the entire range of colours, only three words for numbers.

The OP specifically excluded ConLangs, constructed languages.

Ah, sorry, didn't notice!

[David1917]

Chinese. No morphology to speak of.

In terms of memorization, someone mentioned above the measure words. I do not know how they work in Japanese but in Chinese they are rather intuitive. Moreover, there is a general measure word (个 - "ge") that covers most nouns that don't specifically fall into other categories of measure words, and I've heard native Chinese speakers use it in place of the "correct" measure word.