looking for sb.sb.应用单数还是复数?比如 应该是I'm looking for he 还是I'm looking for him

looking for sb.sb.应用单数还是复数?比如 应该是I'm looking for he 还是I'm looking for him every time i went back looking for sb为什么用looking而不是look~= = ..sb be useful to sb还是for sb? be embarrassing to sb还是for sb? be important to sb还是for sb write for sb还是write to sb 造句：buy sth for sb from sb get sth for sb还是to sb? equip sb with equip sb for sth to sb 还是 sth for sb express sth for sb 还是to sb be rude to sb还是for sb best wishes to sb or for sb available to sb 还是 for sb spare sb./sth.for sb./sth. available to sb 还是for sb send for sb.