请问什么时候用for如:buy sth for sb 什么时候用to如：show sth to sb 力求要细,

请问什么时候用for如:buy sth for sb 什么时候用to如：show sth to sb 力求要细, buy sb sth=buy sth for buy sth for sb. buy sth for 请问是buy sth to sb还是buy sth for sb? is +adj+ for /of to do sth 中,for /of的问题请问it is +adj+ for /of to do sth中,什么时候用of,什么时候用for give sth to sb ,give sth for sb请问什么时侯,用to什么时候用for.请说的明白一点, 请问,拿sth交换sth用英语怎么说?change sth for sth?change sth to sth? 用所给英语句式造句,每个造两句(1)buy sth from+地点(2)buy sb sth(3)buy sth for sb(4)sell sth to sb buy sth for sb 还是 buy sth to sb buy sth to me还是buy sth for me to和for 的结构,如：buy sth for sb.越多分越多,今天之前 请问什么时候用 see sb doing sth 什么时候用 look at sb doing sth什么时候用 watch sb doing sth buy sth.to sb.=buy sb.sth还是 buy sth.for sb.=buy sb.sth好的+++++分 买某物给某人 用英语怎么说是 buy sth for sb 还是 buy sth to sb 怎样用buy sth for sb 造句 造句：buy sth for sb from sb buy sth.for $5 怎么翻译?