Question

they supply extra amount of nutrients to the growing plants
( begin the sentence with extra amount of .......)

Answer 1

The question is asking to change the form of the sentence and follow the guideline provided in the same. We are said to begin the statement with help of the following phrase- "Extra amount of."

Anyhow, the statement after conversion is understated.

Converted sentence: "Extra amount of nutrients are supplied to the growing plants by them."

Here, subject and object interchange their places in order to adhere to the beginning presented in the query.

Answer 2

Extra amount of nutrients is supplied to the growing plants.

This is an example of a sentence in a passive voice.

In a passive voice, it is the action that becomes an important part of a subject, and not the subject itself.

In the first instance, ‘they’ was the subject, but in the answer, we have the action and not the agent getting importance.