due to lack of effective superv**ion,th** company has witnessed quite a large number of fraud cases. 注释: (1)phenomenon 是"现象"的单数形式,不用there h**e been;(2)company has ar**ed 没有这种说法,ar**ed 属严重误拼,英文中不存在这个词. 不妨改成: lots of fraud cases h**e ar**en in ... 20210311