half full

half empty

half over

halfway through

halfway through

in the middle of

to mediate  - mediar 

to be in the middle

to be halfway through

to elapse  - transcurrir, pasar 

to pass  - pasar por, pasar, cruzarse, pasarse, adelantar, pasar (tiempo), transcurrir, ocurrir, aprobar (un examen, una ley), aprobar (en un examen), fallar 

to be a consideration

to come up  - levantarse, (figurado, tema) salir, surgir, ascender, acercarse 

to happen  - pasar, ocurrir, suceder, tener lugar, acontecer, resultar, ocurrir por casualidad