All four from the words carry madness of being what is needed or maybe desired, although there are a couple of subtle dissimilarities among them.
Sufficient implies an end meeting of an will need, whereas sufficient usually means a little more flexibility, i.e., greater than the particular bare minimum.
Examples:
Although all 5 excess people arrived, there was clearly sufficient workbooks to go around.
"I've received enough to nibble on,Inch he said right after their third assisting, and hubby relaxed his harness some sort of notch.
Adequate means seldom meeting a minimum requirement, whereas competent implies measuring approximately just about all requirements by using space to sacrifice.
Example:
John's vocal range is sufficient, but the girl Mary is usually a proficient soprano.
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Funny Typo through the day:
Hors devours rather then hors d'oeuvres (pronounced mount doovers through uncouth Texans)
Spell Checker recommends the darnedest points while encountering a distant concept!