You need to learn the verb patterns. Often they make sense, sometimes you just have to learn them. The patterns are: jemanden/etwas (Akk) lieben jemanden/etwas (Akk) korrigieren But: jemandem (Dat) bei/mit/in etwas (Dat) helfen The rationale is that the dative describes the person who suffers or profits from something, or for whose sake something is done. But that alone is often not enough to guess the correct case. A good dictionary (e.g. Pons) will list the patterns together with their meanings: http://de.pons.com/%C3%BCbersetzung?q=helfen&l=deen&in=&lf= http://de.pons.com/%C3%BCbersetzung?q=korrigieren&l=deen&in=&lf= (In the same way, you should always learn nouns together with the article: "der Tisch" instead of just "Tisch").

Many verbs request accusative, as lieben and korrigieren, others dative, as helfen. So correct ist: Können Sie mich bitte korrigieren? The problem is how to know which one needs accusative and which one dative. Basically, there is no rule, one must know. The questions might help: Wen oder was liebst du/lieben Sie? accusative Wem hilfst du/helfen Sie? dative