1.The e-commerce company is responsible for most online sales in China.
is responsible for負責
She is responsible for the determination of wage levels within this company.
她負責確定這家公司職員的工資標準 。
2.It is also involved in banking and other areas and has just been growing so dramatically that it now accounts for 80 percent of e-commerce in China.
account for(在數量、比例上)占
Together they account for less than five per cent of the population.
他們總共占不到總人口的5% 。