膝を屈する
(膝を屈めるだけの意味なら)to bend one's knees―(礼拝、服従するの意味なら)―bow the knee (to or before god or man)―(屈服するの意味なら)―come to one's knees
膝にくる
to sit knee to knee with one―sit opposite each other
to cross one's legs (tailor-fashion)
to sit knee to knee with one―sit opposite each other
to have a familiar talk with one
膝を組むこと
ひざを折る
ひざを曲げる