have to (verb); must (verb); is indispensable; absolutely necessary
development; evolution; expansion; spreading out; expansion (of an algebraic expression); development (of a three-dimensional shape)
employee; worker; laborer (labourer); blue-collar worker
natural; right; proper; naturally; as a matter of course; rightly
space alien; alien; extraterrestrial being
family; members of a family
sacrifice; victim; sacrifice (to a deity)
to press against; to push against; to force against; to foist on (task, responsibility); to impose (one's will)
(all) at once; at the same time; in one go; right away; in an instant