放不下

not to have room to put sth / to be unable to let go

to have no room to put sth / to be unable to let go

to put / to place / to release / to free / to let go / to let out / to set off (fireworks)

no; not so / (bound form) not; un-

to be not less than (a certain quantity, amount etc)

down / downwards / below / lower / later / next (week etc) / second (of two parts) / to decline / to go down / to arrive at (a decision, conclusion etc) / measure word to show the frequency of an action

cannot stop worrying