单句改错

①Struggled in a world of silence and darkness, Helen Keller seemed to be simple-minded.____

②The three Bronte sisters adopted this practice, Mary Ann Evans did the same.

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③We decided to fight against this unfair system which prohibits us blacks sitting where we like.____

④Our friendship had developed quickly over the weeks that followed.____

⑤Maybe if I studied science then,I would have been able to give you more help.

____

仙人掌的叶适应沙漠干旱生活逐渐变为刺状．这是（　　）

为搜寻马航失联飞机，中国空军2014年4月5日再次派出1架飞机赴南印度洋执行搜寻任务，在任务区域（20°S—26°S、101°E—104°E）发现多块白色漂浮物，并拍照取证。任务海域气象条件复杂，云底高200余米，浪高1-2米。据此完成下列各题。