I am of the opinion that

I think

i.e.

that is

identical

the same

ideology

beliefs; ideas

illustrate

show; draw; picture

illustration

picture

immediately

at once; now; right away

immense

huge; vast

immerse

completely cover

immovable

firm; fixed; set

impartial

fair; just; neutral

impede

hamper; hinder; slow; stall

imperative

pressing; urgent; vital

imperceptible

hard to see; hidden; slight

impersonate

copy; mimic; pretend to be

impetus

push; spur; urge

implement

begin; carry out; do; set up; start

impolite

rude

impotent

helpless; powerless; weak

in accordance with

by; under

in addition

also

in addition to

besides

in all probability

probably

in association with

with

in close proximity to

near

in excess of

more than; over

in favour of

for

in lieu of

instead of

in spite of the fact that

although

in the absence of

without

in the amount of

of

in the course of

during

in the event that

if

in the near future

soon

inaccuracy

error; mistake

inadvertently

without meaning to

inadvisable

risky; unwise

inaugurate

begin; launch

incapacitate

damage; disable; lay up

incarcerate

imprison; jail

inception

beginning; start

incision

cut

incite

cause; goad; prod; rouse

inclement

harsh; nasty; stormy

incompetent

inept; unfit

incomprehensible

baffling; hard to understand

inconceivable

beyond belief; beyond imagining

incorrect

wrong, false

increase

gain; go up; grow; rise

incumbent upon

must

indefinite

uncertain; vague

independent

free; well-off; separate from

indicate

hint; imply; point out; show; suggest

indigenous

native

indignant

angry; upset

indispensable

essential; necessary; vital

individual (adj)

unique; is different for every person (often redun

individual (n)

person; man; woman

individually

on your own; on their own

ineffectual

not effective; useless

inexpensive

cheap; low-priced; low cost; modest

infant

baby

inflexible

firm; rigid; stiff

inhale

breathe in

inherent

innate

inherit

be born with (a disease or condition)

inhibit

check; curb; hinder; slow down

initial

first

initiate

begin; create; open; start

initiative (1)

program, project, plan

initiative (2)

will; motivation; ability to start an activity

injection

needle; shot

injunction

ban; order

innate

inborn; natural

inquire

ask

insecure

unsafe; unsure

institute (v)

begin; set up; start

instrument

agent; means; tool

insufficient

not enough; short of

intention

aim; goal; plan

interact

relate to; work with; get along with

interactions

relationships

intermission

break; pause

interrogate

question; quiz

interrupt

break in; butt in; hinder; stop

intersection

corner; cross street

inundate

flood; overflow

invaluable

valuable; helpful

irrelevant

beside the point, off-base; unimportant

irresponsible

careless, harsh, reckless

irritable

grumpy

issues

concerns; problems; subjects