Students are encouraged to _________ the design competition for robots at the university.

I heard they went skating in themountains last winter. — It _____ true because there was littlesnow there.

It never occurred to meyou could succeed in persuading him to change his mind.

.-Is this beautiful house____-No, it doesn’t belong to____any more She sold it last month.

依次填入下列各句横线处的成语，最恰当的一组是（ ）①精于谋划小圈子的人，拉帮结派，编织自己的关系网，以使自己左右逢源，如鱼得水。结果却是 ___________，到头来圈住的定会是自己。②作为城里人如果错误地认为农村远离城市，对农村污染视而不见，甚至把城市污染物转移到农村，终究要 ___________，用自己的健康来偿还。③机器能够为人类造福，但如果将来机器发展得足够智能，那么人工智能就是“人类最大的潜在威胁”，玩弄人工智能等同于“召唤恶魔”， ___________。