(negative prefix) / not / no

not to be concerned / regardless of / no matter

not only (this one) / not just (...) but also

not so / no / or else / otherwise / if not / How about ...?

unpeaceful / unstable / uneasy / disturbed / restless / worried

insufficient / lacking / deficiency / not enough / inadequate / not worth / cannot / should not

not equal to / not as good as / inferior to / it would be better to

desperately serious / disastrous / extremely / exceedingly

can't help / cannot but

cannot bear / cannot stand / utterly / extremely

from time to time / now and then / occasionally / frequently

it goes without saying / it is self-evident

there is no harm in / might as well

by fair means or foul / by hook or by crook / unscrupulously

not stint / not spare / not hesitate (to do sth) / not scruple (to do sth)

incessantly / without end / more than / not limited to

can't help (doing sth) / can't refrain from

inconceivable (idiom); unimaginable / unfathomable

inevitably

to act against one's will / to have no alternative but to / to have to / to have no choice / must

unwell / indisposed / out of sorts

to have disappeared / to be missing / nowhere to be found

only / merely / no more than / but / however / anyway (to get back to a previous topic) / cannot be more (after adjectival)

not to see / not to meet / to have disappeared / to be missing

fault / blame

no / is not / not

correct / right / not bad / pretty good

incorrect / wrong / amiss / abnormal / queer

cannot / must not / should not

incorrect / erroneous

different / distinctive / unlike

unceasing / uninterrupted / continuous / constant

not enough / insufficient / inadequate

stainless steel

stainless steel

constant / unvarying / (math.) invariant

to withhold / to refuse

not to arrive / not reaching / insufficient / less than

whatever / no matter what (who, how etc) / regardless of / not to discuss

fearless / not worried (by setbacks or difficulties) / even if / even though

not only (... but also...)

resentful / discontented / dissatisfied

to live up to

unstable

motionless

imprecise

dissatisfied

to fail the civil service examination (in imperial China)

unexpectedly

nonfeasance / omission (law)

not very / not particularly

not in detail / not quite clear

should not / to owe nothing

to feel embarrassed / to find it embarrassing / to be sorry (for inconveniencing sb)

real estate / immovable property / immovables

imperfect

unworthy

to pay no attention to / to disregard / to ignore / to let go unpunished / to let off

inadequate / unfit

unwell / feeling ill / to feel uncomfortable / uneasy

not worth

irregular

unlikely to go so far as to / not as bad as

isn't that so?

not good

not to allow / must not / can't

unconsciously / unwittingly

unpredictable eventuality / unpreventable / unavoidable / impossible to overcome / nothing can be done about it / act of God / force majeure

unexpectedly / to one's surprise

in spite of / regardless of

impossible / cannot / not able

unavoidably

not to get along well / to be on bad terms / to be at odds / discord

inconvenience / inconvenient

to disregard / to take no account of

necessary / must have

you're welcome / don't mention it / impolite / rude / blunt

needless to say / it goes without saying

indispensable

used in expressions of the form 照V不誤｜照V不误, in which V is a verb, 照 means "as before", and the overall meaning is "carry on (doing sth) regardless" or "continue (to do sth) in spite of changed circumstances", e.g. 照買不誤｜照买不误, to keep on buying (a product) regardless (of price hikes)

out of the ordinary / out of the common run

there is no lack of

unstable / unsteady

cannot bear or stand / be unequal to / very / extremely

unwilling / unwillingness

not only that, but ...

to not understand / to be puzzled by / indissoluble

no match for / cannot beat

indefinite / unclear

unsymmetrical / asymmetric

not standard / abnormal / irregular

to be dead / to have passed away

(literary) not to speak

not known to anyone / secret / unknown

no longer / no more

abnormal

hard to say / unpleasant to say / can't be sure

not up to much / very indifferent / nothing great about it / nothing good to be said about it

You're welcome / Don't mention it

to have no sense of shame / shameless