concrete jungle
noun [ C usually singular ] uk/ˌkɒŋ.kriːt ˈdʒʌŋ.ɡəl/ us/ˌkɑːn.kriːt ˈdʒʌŋ.ɡəl/
混凝土丛林，水泥丛林（指高楼林立、无树木花草的拥挤城区）
an ugly grey area of a city where people live in closely crowded apartment buildings and there is little space and no trees or grass