I am by no means a master of the English language. (A bit of the opposite actually.) However, I have noticed on numerous occasion how my improper word usage can put a halt to what would have been fluid communication.
Word usage is so important in the Sacraments that they can effect whether or not the Sacrament is "valid and licit."
During the Consecration the form is "This is my Body... This is my Blood..." changing that to what may seem like an equivalent meaning "This is my flowing life force..." can most certainly lead to an illicit if not an invalid Sacrament.
This must also be taken into account when dealing with translations. Often times translating from one language to another, there is not an equivalent word. Great insight is necessary to preserve meaning and usage of that which is being translated.