This is just one of those fun things about language, I suppose. Anytime you have the word "to help", the word that comes after it should be in the subjunctive tense (i.e. the infinitive with the word "to" removed).
"Can you please help me cook?"
"Can you help me answer this question?"
"Can you help me to cook" would be right when translated into certain languages, but not in English.
Other verbs that typically require this construction include can, must, and will:
"I can tell you the answer."
"I will run five miles later."
"You must try this cake!"
Brett Beach-Kimball | Manhattan GMAT Instructor
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