英和和英

absolutely essential

crucially important

vitally important

vitally important

to be necessary

being indispensable

to be weighty and important

of extreme importance

be the essential element

It is an important matter―a matter of importance―a matter of moment.

to a crucial degree

becoming important

significant

a necessary or essential thing

the degree of indispensability

being of vital importance

being of crucial importance

have need of

a necessary thing

an indispensable duty

of vital importance

of paramount importance

in great necessity

this is vitally important

of primary importance

be of importance

an essential item

of something or someone, to be an absolutely necessary part of something

of something, to be needed

an indispensable implement