Here are examples of the word/phrase "inadequate" used in a sentence and paraphrased in a sentence...
He applied for a job but his credentials were inadequate.
He applied for a job but his credentials were not good enough.
That amateur fighter could not defeat the master martial artist because his skill was inadequate.
That amateur fighter could not defeat the master martial artist because his skill was insufficient.
You better give it your all because sandbagging vs him would be inadequate.
You better give it your all because sandbagging vs him would be insufficient.
Other Examples...