A:It's time to get up.
B:It's time to have lunch.
Great________have been made to make our environment more and more beautiful.
下列有关上海的自然环境的说法,正确的有( )
①位于长江三角洲 ②以亚热带季风气候为主
③河湖众多 ④地势崎岖高峻