1
                           general:: 
                            Phrase(s): knock against someone or something 
to bump against someone or something.  •  Mickey knocked against Mary and said he was sorry.  •  I didn’t mean to knock against your sore knee., Phrase(s): knock something against something 
to strike something against something.  •  He knocked a chair against the table and tipped both pieces of furniture over.  •  A chair was knocked against the table, upsetting a vase., Phrase(s): knock (up) against someone or something 
to bump against someone or something.  •  The loose shutter knocked up against the side of the house.  •  The large branch knocked against the garage in the storm.
                        
                        
 
                        
                            McGrawhill's American Idioms And Phrasal Verbs