Types of uninflected words

In Sanskrit, we often modify a word's sounds to change its meaning. We often modify both verbs:

• गम् → गमिष्यसि
  gam → gamiṣyasi
  go → You will go.
  

And nominals:

• नर → नरेषु
  nara → nareṣu
  man → among the men
  

These kinds of changes are called inflection. Sanskrit uses inflection extensively, so it is sometimes called a highly inflected language.

Sanskrit also has a large class of words that we can call uninflected words (avyayāni, “unchanging”), sometimes also called indeclinables in English. These words are “fixed” in a way that nominals and verbs are not. Uninflected words can still go through sandhi changes, but otherwise, they always stay the same:

• त्वं न गच्छसि।
  tvaṃ na gacchasi.
  You do not go.
  

• अहं न गमिष्यामि।
  ahaṃ na gamiṣyāmi.
  I will not go.
  

• गजा न गच्छेयुः।
  gajā na gaccheyuḥ.
  The elephants might not go.
  

Types of uninflected words

There are a few important categories of uninflected words.

First are what we might call prepositions. In English, this term refers to words like “over,” “under,” “around,” and so on. In Sanskrit, this term refers to words that are usually used as verb prefixes:

• गच्छन्ति → आगच्छन्ति
  gacchanti → āgacchanti
  They go. → They come (“go here”).
  

• गच्छन्ति → संगच्छन्ति
  gacchanti → saṃgacchanti
  They go. → They meet (“go together”).
  

Prepositions are part of a larger class of words call nipātāḥ, which are miscellaneous words:

• रामः सीता च
  rāmaḥ sītā ca
  Rama and Sita
  

• हे राम त्वं कुत्र?
  he rāma tvaṃ kutra?
  Hey Rama! Where are you?
  

Finally, we have adverbs, which modify the verb in some way. Many of them are created from adjectives:

• मन्द → मन्दम्
  manda → mandam
  slow → slowly