Question

Did you write this letter? write into passive form​

Answer 1

Explanation:

A lichen is not a single organism; it is a stable symbiotic association between a fungus and algae and/or cyanobacteria. Like all fungi, lichen fungi require carbon as a food source; this is provided by their symbiotic algae and/or cyanobacteria, that are photosynthetic.

Answer 2

Answer:

A letter is being written [by me].