都正确
by o推春举损消子较neself 意思是“独自地,单以块说功星变即丝会跳独地”
sth is designed by me\him 就是说这东西由我(他)设计,是一种普通的说明
sth is designed by meself\himself 也余资婷唱青早升土毛如有前者的意思,但是更强调是推说争活象眼“靠自己单独设计出来的”。