"at sb.'s request"

"at sb.'s request" keep distance from sb./sth.at sb's request up to now~request 英语翻译 翻译以下短语并完成句子. 1) on request _ 2) by request of _ 3)at sb at sb's own expense request sb.to do造句 as your request at your request 区别 have sb. at one’s back造句 have sb.at one’s back造句 both jack's request and Mike's own能不能换成 at both jack and Mik request.s是什么 request 的句型是什么?request sb to sth? request sb to do与request to do的区别