变幻莫测 | biàn huàn mò cè | to change unpredictably / unpredictable / erratic / treacherous | |
反复无常 | fǎn fù wú cháng | unstable / erratic / changeable / fickle | |
疯疯癫癫 | fēng feng diān diān | deranged / erratic | |
飘忽不定 | piāo hū bù dìng | to drift without a resting place (idiom) / roving / errant / vagrant / erratic |