它補充說道：中國被認為從背後盜取了其中的50-80%
PS：我看了原文
“claimed that IP theft was costing the US an estimated $300bn each year.It added that China was thought to be behind 50-80% of the theft.”
它是聲稱“知識產權剽竊”使得美國每年在軟件行業上損失大概3000億美元，其中中國的軟件盜版占這個損失中的50-80%，即1500億到24000億元。
希望幫助到妳！