Question

I write the letter_blue ink.
(Add preposition)​

Answer 1

Answer:

I write the letter with blue ink.

Answer 2

Answer:

I wrote the letter by blue ink

by is the preposition

Explanation:

Prepositions and postpositions, together called adpositions, are a class of words used to express spatial or temporal relations or mark various semantic roles. A preposition or postposition typically combines with a noun phrase, this being called its complement, or sometimes object.