The word "垂死挣扎" is formed by combining "垂死", meaning "dying" or "on the verge of death", with "挣扎", meaning "to struggle". The characters "垂" (approaching) and "死" (death) create the modifier "垂死" to describe a state, while "挣" and "扎" together form the verb "挣扎" for the action, resulting in a literal meaning of a desperate final struggle against imminent death.