Ill make it simple.
You go to the doctor and he tells you to fill out insurance forms which are in English, Those forms include your medical history
Those forms are in English
The doctor takes your blood test and tells you , that you have High Cholestoral and gives you liptor. You cannot read the directios on the bottle that says you cannot take grapefruit with a Statin which is chemisry . So you need to know english and chemistry or it could kill you.