Explanation

āύāĻŋāĻšā§‡āϰ āĻŦāĻžāĻ•ā§āϝāϟāĻŋ passive voice āĻ āϞ⧇āĻ–āĻž āĻšā§Ÿā§‡āϛ⧇:
“Trees are considered one of our best friends.”

Passive voice āĻĨ⧇āϕ⧇ active voice āĻ āϰ⧂āĻĒāĻžāĻ¨ā§āϤāϰ āĻ•āϰāĻžāϰ āĻŽā§‚āϞ āύ⧀āϤāĻŋ āĻšāϞ⧋:
1. āϝ⧇āχ āĻŦā§āϝāĻ•ā§āϤāĻŋ āĻŦāĻž āĻŦāĻ¸ā§āϤ⧁ āĻ•āĻžāϜāϟāĻŋ āĻ•āϰ⧇, āϤāĻžāϕ⧇ subject āĻ āφāύāϤ⧇ āĻšāĻŦ⧇ (agent → subject)āĨ¤
2. āĻŽā§‚āϞ verb āϕ⧇ active āĻĢāĻ°ā§āĻŽā§‡ āĻŦā§āϝāĻŦāĻšāĻžāϰ āĻ•āϰāϤ⧇ āĻšāĻŦ⧇ (āϕ⧋āύ auxiliary āĻŦāĻž past participle āύāĻž āϰ⧇āϖ⧇)āĨ¤
3. āĻŦāĻžāĻ•āĻŋāϰāĻž object āĻŦāĻž complement āĻšāĻŋāϏ⧇āĻŦ⧇ āĻĨāĻžāĻ•āϤ⧇ āĻĒāĻžāϰ⧇āĨ¤

āĻāχ āĻ•ā§āώ⧇āĻ¤ā§āϰ⧇ agent āĻŦāĻž āĻ•āĻžāϜāĻ•āĻžāϰ⧀ āĻšāϞ⧋ “we” (āφāĻŽāϰāĻž), āĻ•āĻžāĻœā§‡āϰ āĻŦāĻŋāώāϝāĻŧ (object) āĻšāϞ⧋ “trees” (āĻ—āĻžāĻ›āϗ⧁āϞ⧋), āĻāĻŦāĻ‚ āĻŦāĻžāĻ•āĻŋāϰ āĻ…āĻ‚āĻļ āĻšāϞ⧋ “one of our best friends” (āφāĻŽāĻžāĻĻ⧇āϰ āϏ⧇āϰāĻž āĻŦāĻ¨ā§āϧ⧁āĻĻ⧇āϰ āĻŽāĻ§ā§āϝ⧇ āĻāĻ•āϟāĻŋ)āĨ¤ āϤāĻžāχ Active voice āĻ āĻŦāĻžāĻ•ā§āϝāϟāĻŋ āĻšāĻŦ⧇:
“We consider trees one of our best friends.”

āĻ…āĻ¨ā§āϝāĻžāĻ¨ā§āϝ āϏāĻŽā§āĻ­āĻžāĻŦā§āϝ āϰ⧂āĻĒāϗ⧁āϞ⧋ āϕ⧇āύ āωāĻĒāϝ⧁āĻ•ā§āϤ āύ⧟, āϤāĻž āĻĻ⧇āĻ–āĻž āϝāĻžāĻ•:
- “It is tree which is our best friend.”
â€ĸ āĻāĻ–āĻžāύ⧇ āĻ—āĻžāĻ›āϕ⧇ “it” āĻĻāĻŋāϝāĻŧ⧇ āύāĻŋāĻ°ā§āĻĻ⧇āĻļ āĻ•āϰāĻž āĻšāϝāĻŧ⧇āϛ⧇, āĻāĻ•āĻĻāĻŽ āύāĻŋāĻ°ā§āĻĻāĻŋāĻˇā§āϟ āĻāĻ• āĻ—āĻžāĻ› āĻŦ⧁āĻāĻŋāϝāĻŧ⧇āϛ⧇, āĻ…āĻĨāϚ āĻŽā§‚āϞ āĻŦāĻžāĻ•ā§āϝ⧇ āĻ—āĻžāĻ›āϗ⧁āϞ⧋āϕ⧇ āĻŦāĻšā§āĻŦāϚāύ⧇ (‘trees’) āωāĻ˛ā§āϞ⧇āĻ– āĻ•āϰāĻž āĻšāϝāĻŧ⧇āϛ⧇āĨ¤
â€ĸ “which is our best friend” āĻ…āĻ‚āĻļāϟāĻŋāĻ“ āĻŦāĻžāĻ•ā§āϝāϟāĻŋāϕ⧇ āϜāϟāĻŋāϞ āĻ“ āĻ…āĻĒā§āϰāϝāĻŧā§‹āϜāύ⧀āϝāĻŧ āĻ•āϰ⧇ āϤ⧋āϞ⧇āĨ¤

- “Trees are our best friends.”
â€ĸ āϝāĻĻāĻŋāĻ“ āĻ…āĻ°ā§āĻĨ āϟāĻžāĻ¨â€“āĻŽā§‡āϟāĻžāύ⧇ āϕ⧋āύ⧋ āϏāĻŽāĻ¸ā§āϝāĻž āύ⧇āχ, āĻ•āĻŋāĻ¨ā§āϤ⧁ āĻāϟāĻŋ āĻŽā§‚āϞ āĻŦāĻžāĻ•ā§āϝ⧇āϰ passive voice āĻĨ⧇āϕ⧇ āϏāϰāĻžāϏāϰāĻŋ Active voice āĻ āϰ⧂āĻĒāĻžāĻ¨ā§āϤāϰ āύāϝāĻŧāĨ¤
â€ĸ āĻŽā§‚āϞ āĻŦāĻžāĻ•ā§āϝ⧇ āĻ›āĻŋāϞ “considered one of our best friends” – āĻāĻ–āĻžāύ⧇ “one of” āĻ…āĻ‚āĻļāϟāĻŋ āĻŦāĻžāĻĻ āĻĒāĻĄāĻŧ⧇ āϗ⧇āϛ⧇āĨ¤

- “We considered trees one of our best friends.”
â€ĸ āĻāĻ–āĻžāύ⧇ tense-āĻ āϏāĻŽāĻ¸ā§āϝāĻž āφāϛ⧇ – āĻŽā§‚āϞ āĻŦāĻžāĻ•ā§āϝ⧇ āĻŦāĻ°ā§āϤāĻŽāĻžāύ āĻ•āĻžāϞ (present simple) implied, āĻ•āĻŋāĻ¨ā§āϤ⧁ “considered” āϞāĻŋāϖ⧇ past tense āĻŦā§āϝāĻŦāĻšāĻžāϰ āĻ•āϰāĻž āĻšāϝāĻŧ⧇āϛ⧇āĨ¤

āϏ⧁āϤāϰāĻžāĻ‚ āϏāĻŦ āĻĻāĻŋāĻ• āĻŦāĻŋāĻŦ⧇āϚāύāĻž āĻ•āϰ⧇ āϏāĻ°ā§āĻŦā§‹āĻ¤ā§āϤāĻŽ Active voice āϰ⧂āĻĒ āĻšāϞ⧋:
“We consider trees one of our best friends.”

āϏāĻ‚āĻ•ā§āώ⧇āĻĒ⧇,
1. passive āĻŦāĻžāĻ•ā§āϝ⧇ āĻĨ⧇āϕ⧇ agent (we) → subject āĻ āύāĻŋāϝāĻŧ⧇ āφāϏāĻž,
2. āĻŽā§‚āϞ verb (consider) āϕ⧇ āϏāϰāĻžāϏāϰāĻŋ Active āĻĢāĻ°ā§āĻŽā§‡ āĻŦā§āϝāĻŦāĻšāĻžāϰ,
3. āĻ—āϤāĻŋāĻŦāĻŋāϧāĻŋāϰ āϏāĻŽāϝāĻŧ (present tense) āĻ…āĻ•ā§āώ⧁āĻŖā§āĻŖ āϰāĻžāĻ–āĻž āĻāχ āϧāĻžāĻĒāϗ⧁āϞ⧋ āĻŽā§‡āύ⧇ Active voice āĻŦāĻžāĻ•ā§āϝ āĻ—āĻ āύ āĻ•āϰāϞ⧇ āφāĻŽāϰāĻž āĻĒāĻžāχ:
“We consider trees one of our best friends.”