Unpopular opinion: Declension and conjugation are nice! It means different forms for the act of watching X (watching birds), X that is watching (watching eyes), or X that is used for the act of watching (watching post). So you immediately know which one is which, instead of trying to figure that out from context (you have 200 milliseconds before the next sentence starts, good luck).
In English it's not based on context, it's based on word order. Declension is a cool concept but it's far more confusing to foreigners because word order basically doesn't matter.
For example in Czech:
Jan zabil Petra
Jan Petra zabil
Petra Jan zabil
Petra zabil Jan
Zabil Petra Jan
and
Zabil Jan Petra
are all equivalent to the English "John killed Peter." Change Jan to Jana and Petra to Petr and all 6 of those become "Peter killed John." Even more confusing to a foreigner learning it is that Petra and Jana are the feminine forms of those names in the nominative case.
