When a writer does not know who performed the action in a sentence, the writer can still write a grammatically correct sentence by

using the active voice.
using the passive voice.
ending the sentence with an infinitive.
ending the sentence with a preposition.

Using the passive voice

Explanation:

Ex:

Rice is grown in China.  (You don't know who grew the rice.)

Based on the information given, the passive voice can be used by the person.

A passive voice simply means the form of verb where the subject undergoes the action of the verb.

In a situation where the writer does not know who performed the action in a sentence, then the writer can still write a grammatically correct sentence by using the passive voice.

Learn more about passive voice on:

link

the answer is mary made mudpies on monday.

remember alliteration is the occurrence of the same letter or sound at the beginning of adjacent or closely connected words.  

you need to make an explanation. so, since you did not include one, so no one, and i mean no one can unfortunately you,