Poem Lies, Essay on it Options

[Chreal]

I need to write an essay for English about this poems. I need to know the poetic device for this poem and it's theme.

Lies Telling lies to the young is wrong
Proving to them that lies are true is wrong
Telling them that God's in his heaven and
all's well with the world is wrong.
The young know what you mean. The young are people.
Tell them the difficulties can't be counted.
and let them see not only what will be
but see with clarity these present times.
Say obstacles exist they must encounter sorrow happens,
sorrow happens, hardship happens.
The hell with it. Who never knew
the price of happiness will not be happy .
Forgive no error you recognize,
it will repeat itself, increase,
and afterwards our pupils
will not forgive in us what we forgave.
-Yevgeny Yevtushenko

Thanks