非洲最大的盆地是（ ）

焉耆马是我国古代西域名马，体型较小，善奔跑，耐力好，这些特征与其所处环境密切相关。焉耆马集中产自天山海拔2800米处高山盆地，此盆地由三个“U”形谷组成。下图为“我国天山自然带分布图”。据此完成以下问题。

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    The summer vacation is the best time for students．They can go outdoors and have fun．They can go to big cities to  1，or go to the countryside to 2the beauty of nature(大自然)．

    Peter is an American middle school student and he loves 3  very much．He always travels in his country．

    This summer vacation he wants to do4．He is interested in Chinese history． 5he is flying to Beijing and Xi'an for the summer vacation．He is leaving on l2th July and 6 New York on the last day of the month．He plans 7 a fantastic vacation．During the 8，he is visiting places of interest and going shopping．At night，he is  9  to enjoy the night views．,He is sure he will have a  10 time．

 酸奶是一种健康的发酵食品，制作酸奶需要多长时间？制作的最适温度是多少？生物兴趣小组打算一探究竟．