客串

to appear on stage in an amateur capacity / (of a professional) to make a guest appearance / (fig.) to assume a role outside one's usual duties / to substitute for

customer / visitor / guest

to string together / to skewer / to connect wrongly / to gang up / to rove / string / bunch / skewer / classifier for things that are strung together, or in a bunch, or in a row: string of, bunch of, series of / to make a swift or abrupt linear movement (like a bead on an abacus) / to move across

special guest performer (in a show) / special guest appearance (in film credits)