The phrase "gives one all" typically implies a sense of completeness or full effort. Its antonyms, therefore, may include words that indicate a lack of effort or incompleteness. Some possible antonyms could include words like "half-hearted", "lazy", "half-baked", "inadequate", "insufficient", "minimal", "slapdash", or "careless". These words all suggest a sense of incompleteness, insufficiency or lack of effort, which is the opposite of the sense of completeness or full effort conveyed by the original phrase. By using antonyms in this way, we can convey a sense of contrast and emphasize the importance of effort and dedication in achieving our goals.