シャツを脱いで横になってください。

shirt (underwear); undershirt; singlet; shirt (outerwear, esp. dress shirt)

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to take off (clothes, shoes, etc.); to undress

horizontal (as opposed to vertical); lying down; side-to-side (as opposed to front-to-back); width; breadth; side (of a box, etc.); beside; aside; next to; unconnected

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 become; to get; to grow; to be; to reach; to attain; to result in; to prove to be; to consist of; to be composed of; to succeed; to be complete; to change into; to be exchanged for; to play a role; to be promoted; to do ...

to give; to confer; to bestow; to kindly do for one; to oblige; to favour; to favor