quieto

adj. quiet, silent, noiseless; peaceful, tranquil; still

v. calm, calm down, quiet, quiet down

adj. halcyon, quiescent, calm, still

v. lay

interj. hush

v. quiet, make silent; calm; remain silent, become quiet

= still, unmoving, motionless.
Ex: He sat still, full in the eye of the sun, and meditated.
Ex: The dynamic path generation problem of robots in environments with other unmoving and moving objects is considered.
Ex: In a control condition, participants recited memorized text to the research assistant who sat motionless.
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* no poder estarse quieto = have + the fidgets, fidget.
* quedarse quieto = stand + still, stand by.