書類は内ポケットにしまっておけ。

documents; official papers

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

inside; within; while; among; amongst; between; we (referring to one's in-group, i.e. company, etc.); our; my spouse; imperial palace grounds; emperor; I (primarily used by women and children); me

pocket

at (place, time); in; on; during; to (direction, state); toward; into; for (purpose); because of (reason); for; with; by; from; as (i.e. in the role of); per; in; for; a (e.g. "once a month"); and; in addition to; if; although

to finish; to stop; to end; to put an end to; to bring to a close; to close (a business, etc.); to close down; to shut down; to shut up; to put away; to put back; to keep; to store; to finish ...; to do ... completely