(product development) project

largely; mostly

a lot / a majority

project (planned endeavour)

toilsome, painstaking / worrisome

to toil, to work hard / to worry

toil, hardship / worry, anxiety

complete

completion, accomplishment

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend