To decline to comment or not express an opinion; to not indicate whether one agrees or disagrees.

To be beyond doubt; there is no denying that something is true.

to not express an opinion; to remain neutral by not indicating whether one agrees or disagrees

not known whether a certain course of action is feasible or acceptable

to refuse to say whether one agrees or disagrees; to not express an opinion

To suggest what is feasible and discard what is not; refers to advising a ruler or superior on what should be adopted or abolished.