求英语解:he works during the day;he works during the week;he works on the weekends

问题描述:

求英语解:he works during the day;he works during the week;he works on the weekends
请问可以用he works during the days;he works during the weeks吗?
为何weekends 为复数?

因:
weekend
英[ˌwi:k'end] 美[ˈwikˌɛnd]
n.周末;星期六和星期日(或略长一点的)休息时间
所以during the weekends必是复数