The protest got out of hand and many police officers tried to hold the protestors ..... behind the barricade. (*) back (*) backing (*) backs (*) backed
This is a companion discussion topic for the original entry at https://english.best/questions/19760,the-protest-got-out-of-hand-and-many-police-officers-tried-to-hold-the-protestors-___-behind-the-barricade/