Answer: "I" in both cases.
Explanation: In English, there are three different kinds of cases in the uses of pronouns: nominative (or subjective), objective and possessive. The nominative case is when the pronoun acts as the subject of a sentence (this pronouns are I, you, he/she/it, we, they and who). The objective case is when the pronoun acts like the object of a sentence (they are me, you, him/her/it, us, them and whom). And the possessive case are pronouns that show that something belongs to someone (they are my, your, his, her, its, their, our, mine, yours, his, hers, ours, and theirs). In the given sentences, the pronouns that are lacking, are in the subject of the phrase, so the correct answer is "I".
