放空擋

to coast along in neutral gear (in a car) / (coll.) to go commando

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

to relax completely / to empty one's mind / (finance) to sell short / (of a commercial vehicle) to travel empty (no cargo or passengers) / to deadhead

empty / air / sky / in vain

to empty / vacant / unoccupied / space / leisure / free time

neutral gear

to resist / to obstruct / to hinder / to keep off / to block (a blow) / to get in the way of / cover / gear (e.g. in a car's transmission)

to arrange / to put in order