lead / direction / direct

act in concert with / go into partnership with / cooperate with / fall in line with / tie up with

comrade / company

swear / say definitely / explain / declare / assert / affirm

be absolutely sure about *something

say definitely / say positively / assert / affirm / declare

practice / drill

training / discipline / drill

dirt / trash / junk / garbage / rubbish / litter

(of things that are chafing against one another) with a squeak / (of things that are chafing against one another) with a creak / (of things that are chafing against one another) with a grind