失去精力weak

• 神经衰弱

  nervous exhaustion

• 衰弱的身体

  feeble body

• 病后体力衰弱

  body is very weak after the illness

• 身体衰弱下去了

  body has weakened

• 病人非常衰弱

  the patient is extremely weak

• 老人渐渐衰弱下去

  elderly people get gradually weaker

事物由强转弱diminishing