To resolve that, try to have a sufficient amount of sleep so that both your body and mind will keep fit.

sufficient 是形容词，意思是"足够的、充足的"，来自拉丁语词根 sufficere（满足）。这个词由前缀 suf-（sub-的变体，表示"在...之下"）和词根 ficere（做、制造）组成，字面意思是"做到满足"。