So far, I have talked about the article "a" and "an" in English following the same rule in usage before constants and vowels, but with a difference, that instead of using "a" and "an" for an article of singularity, in Sanskrit it is used as a prefix to make an opposite of a noun and an adjective - both used as nominatives or subjectives. If the word begins with a constant, "a" is used, and if the word begins with a vowel, then "an" is used!
Here in this posting I will talk about 3 more rules in English, that have their roots in Sanskrit, besides the one mentioned before - all are my observations.
To make a word into a comparative in English, the suffix "er" is used, e.g., cheap-er, and to make a word into a superlative, the suffix "est" is used, e.g. cheap-est. Guess what, in Sanskrit, for comparatives, suffixes "tar", "iyas", "iyar" or "iyah" are used, and for superlatives, suffixes, "tam" and "iyast" are used. The sound of Sanskrit "i" sounds like "e" in English, and often in Sanskrit, "i" becomes "y" before some vowels, as part of some degradation of their grades. So one can see that "er" and "est" are nothing but the remanants of Sanskrit suffixes, which I guess would also be there in Ancient Greece, Latin and other Indo European branches. In one of the postings, I would comment on my thoughts, why Sanskrit, in my view is the oldest of all IE surviving languages.
Also, in English, to make an "action" noun into an "agent" noun, suffixes "ar", "er", "or" are used. In Sanskrit, the sound "ri" is used to make it into a general root, like from verb root "pa", to protect, one gets a participle "action" noun, as "pita" and "agent" noun as "pit-ri", which then is declined to become "pita", "pitah", "pitar", "pituh", "pitur", and so on. There is another rule, where the suffix "ri" becomes "ir" sometime. I am not going into all the cases for all numbers, but you get the idea, that "ar", "ir" and "ur" are what makes the English endings. There is a rule where "a" and "u" combined, will make an "o" sound, so one can see "ur" becoming "or" sound.
Now to make some word in English into an opposite, we would use "un", "in, "im", "ir", "il". People who noticed how the same vowel sounds get mixed up with neighbouring vowels, would realize "a" can become "e", "i" and also convoluted suppressed sound of "u"! Think people saying Ram, as Rim, Rem, and Rum. So the Sanskrit sound of "an" used as a suffix to make a negative, would then become "in", and "un", where sound "e" is nothing but "a" and "i" combined in euphonics. Now if a word begins with "m", "r", or "l", the "n" in "in" would become "m", "r" or "l" respectively. This accounts for the suffixes, "im", "ir" and "il" besides, the suffix "in" and "un". This rule is like one of the rules in Sanskrit Sandhi!