Answer:
The letter <u>was written</u> yesterday.
Explanation:
Yesterday is a keyword that indicates the action happened and ended. Therefore, we have to use past simple tense.
That leaves us with <u>wrote</u> and <u>was written</u> choice. Last two choices are past perfect and they should only be applied when there consists of past tense in one clause —> e.g I had eaten rice before I went to bed.
Next, we have to understand between active voice and passive voice.
Active Voice
Subject + Verb + Object
An example of active voice is:
- I eat rice.
- I write a book.
- I hit a desk.
On the other hand, we have:
Passive Voice
Object + verb to be/have + been (if there is) + past participle + by subject (if there is)
An example is:
- Rice is eaten by me.
- A book is written by me.
- A desk is hit by me.
Active voice starts with subject causing something to object.
Passive voice starts with object being caused something by subject.
And we know that a letter cannot write itself so it cannot be a subject but an object.
Hence, the letter was written yesterday is correct, indicating that the letter was being done and not letter doing.
