Not exact

Shadows are not exact but real You can’t force it or conceal It may be even longer than size You must think it wise It may accompany where you go and turn You stand, sleep or even run It has same strength and reflection Think over it and base your action A tree’s shadow proves it is standing. A bird follows its shadow and knows it is flying. My shadow proved that I have existence I am living in present tense What has it do with my being on earth? I cease to exist upon natural death I follow on every step and prove That I am real and follow or move The story doesn’t end with non existence Its impact may follow even without insistence People may follow on what has been left behind They will try to know the shadow of wisdom and find So it stays even if you are dead Your message is accepted and widely read Single word is enough to give impetus or lead You have formed some link by providing the thread