Scientists has already warned us again and again,it's bad for us to eat too many sweets.
错误2处

首先Scientists是复数,后面的has应该是have才对;

again and again后面的","应该改成that,由它引导宾语从句it's bad for us to eat too many sweets;
你好!
重复地
repeatedly 英[r?'pi:t?dl?] 美[r?'pi:t?dl?]
adv. 反复地,重复地; 再三地; 屡次地; 不停地;
[例句]Both men have repeatedly denied the allegations
两个人都一再否认指控。


