Yeah no shit. That's the hard part.
That's pretty easy for adults to learn. No need to learn anything else, just the word itself
And you need to conjugate them based on what tense it is. For example the verb eat is "eat" normally, "ate" on past participle, and then "eaten" on the other one (whatever it's called).
That's one of the few things that do conjugate. However, English verbs are still lacking in features. No special form for imperative, conditional, potentional, etc.
Also nouns don't change (except for plural).
If you compare English to Finnish for example, the verbs and nouns show way more information than English counterparts do.
Example noun:
Kotonani
Koti = house
Kotona = in (a) house
Kotonani = in my house
Example verb:
Juoksentelisinkohan = I wonder if I should run around aimlessly
Juosta = to run
Juoksen = I run
Juoksentelen = I run around aimlessly
Juoksentelisinko = should I run around aimlessly
Juoksentelisinkohan = I wonder if I should run around aimlessly
Also English lacks common stuff like question particles/suffixes
In Japanese for example, you put -ka at the end of the sentence and it becomes a question. In English you rely on word order.
Languages like finnish, Turkish, Russian have free word order because the grammar is more complex so you can switch the places of words.
