push string uphill
waltz
hard yards
make bricks without straw
nail Jell-O to a tree
have a mountain to climb
beaver away
get over the line
get blood out of a stone
waste of time
queer someone's pitch
plough on
mountain
job
iron man
picnic
get over
miracle worker
put a hat on a hat
slog
sprezzatura
piss up a rope
lightning in a bottle
stroll
see daylight
constipation
stultification
deadening
get the job done
impairment
wherewithal
pull off
botch
pull teeth
square one's shoulders
carry coals to Newcastle
polish a turd
order of business
square the circle
chapter
occasion
mission impossible
go through the motions
futilely
grind
rush job
draw the short straw
mug's game
stresslessly
ticking-over