is aware (verb) heed: give care, thought to
Sinonime: brief, changeable, deciduous, emigrating, ephemeral, evanescent, flash, fleeting, flitting, fly-by-night, flying, fugacious, fugitive, going by, impermanent, insubstantial, migrating, momentary, moving, passing, provisional, short, short-lived, short-term, temporal, transitory, transmigratory, unstable, vacating, volatile
Antonime: enduring, lasting, permanent