This is the 7525th most frequent Polish word.
krzywej
"Krzywej" means "of a curve" (genitive form in Polish).
In this sentence, 'krzywej' is the genitive case of the adjective 'krzywa', agreeing with the noun 'linii'. It describes the attribute of the line being curved.
Krzywej linii nie da się łatwo wyprostować.
A curved line cannot be easily straightened.
Here, 'krzywej' is used in the genitive case to indicate possession, showing that the 'ostrość' (sharpness) refers to the 'krzywej' (curve).
Podczas jazdy samochodem należy uważać na ostrość krzywej.
While driving, one should be cautious of the sharpness of the curve.
In this sentence, 'krzywej' is in the locative case, denoting the location or context within which the graphs are prepared.