Is this good for passive voice? The president was trying to develop his country's economy.

No. The verb "was trying" is in the active voice because the president is doing the action.

Please try again for a good sentence using the passive voice. Follow the pattern used in the websites I posted.

Yes, the sentence "The president was trying to develop his country's economy" is an example of the passive voice. In passive voice, the subject of the sentence becomes the recipient of the action, rather than the doer of the action.

To identify whether a sentence is in passive voice, you can follow these steps:

1. Look for the form of the verb "to be" (e.g., is, am, are, was, were) followed by the past participle of a verb (e.g., trying, developed).
2. Check the order of the sentence: if the object or recipient of the action comes before the verb, it indicates the passive voice.
3. Compare to active voice: if the subject of the sentence performs the action directly, rather than having the action done to it, it is in active voice.

In the given sentence, "was" (the past tense of "to be") is followed by the past participle "trying," indicating the passive voice. Additionally, the subject "the president" is the recipient of the action ("trying to develop his country's economy") rather than the doer.

Note: While passive voice has its usage, it is generally recommended to use active voice for clearer and more direct communication.