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In my book I have this sentence:
生徒が学校へ行こうと思って野を歩いていると、一ぴきのきつねが遠くにいるのをみた。
I understand the sentence, "The student, who is walking in the field while he wants to go to school, saw a fox far away".
But what's the purpose of "と" here?
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と in this case implies that something unexpected is following. "The student was walking in the field to go to school, when he saw a fox far away." Or we can emphasize like that to see the nuance: "Just when the student thought of going to school and was walking in the field, he saw a fox far away."
生徒が学校へ行こうと思って野を歩いていると、一ぴきのきつねが遠くにいるのをみた, not 「生徒が学校へ行こうと思って野を歩いていると、一匹のきつねが遠くにいるのが見えた 」 or 「～～、一匹のきつねが遠くに見えた 」? – Chocolate♦ Jul 4 '17 at 22:49