3. (Who/Whom) can point out Lake Ontario, where the S t Lawrence River originates

The St. Lawrence River originates at the outflow of Lake Ontario between Kingston, Ontario, on the north bank, Wolfe Island in mid-stream, and Cape Vincent, New York.

Explanation:

modal adverbs are used to modify specific verbs that consist of a linking verb (verb of being) and sometimes another verb. examples of modal verbs include can, could, may, might, must, shall, should, will and would.

modal auxiliary. an auxiliary verb characteristically used with other verbs to express mood, aspect, or tense. in english, the most common modal auxiliaries are can, could, may, might, must, ought, shall, should, will, and would. also called modal .

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