Explain how Percy Bysshe Shelley relates the skylark's song to his own efforts to write poetry in "To a Skylark."

Hail to thee, blithe spirit! 
Bird
thou never wert- 
That from heaven or near it 
Pourest thy full
heart 
In profuse strains of unpremeditated art. 

That first
stanza of Shelley's poem calls the bird's song "unpremeditated art." In other words,
human poets have to premeditate, have to think about what they're going to write. But
the skylark's music pours out naturally without the bird having to think about it ahead
of time. 

Teach us, sprite or bird, 
What sweet thoughts are
thine: 
I have never heard 
Praise of love or wine 
That
panted forth a flood of rapture so divine. 

In that stanza (which
comes much later in the poem, I've skipped over quite a few stanzas) "Praise of love or
wine" means "poems that human artists have written praising the joys of love and the
pleasures of wine." The speaker or this poem, the human poet addressing the skylark, is
saying, "The joy and pleasure that you pour forth in your song is greater than any
expression of joy and pleasure that I have ever come across in any poem by a human
author." 

Chorus hymeneal, 
Or triumphal
chant, 
Match'd with thine would be all 
But an empty
vaunt- 
A thing wherein we feel there is some hidden
want. 

A "Chorus hymeneal" is a poem that celebrates a wedding. A
"triumphal chant" is a poem that celebrates a military victory. Shelley's poem is saying
that the joy expressed in a wedding poem or a victory poem sounds like "But an empty
vaunt" (just a meaningless boast) compared to the skylark's song. A "hidden want" is
some lack, some shortcoming that can be felt but can't quite be defined. So the last
line of that stanza is saying that even the most celebratory human poetry seems to be
missing something when measured against ("Match'd with") the bird's
singing. 

Teach me half the gladness 
That thy brain must
know; 
Such harmonious madness 
From my lips would
flow, 
The world should listen then, as I am listening
now. 

In the final stanza of the poem, the speaker says, "If I were
filled with even half as much beauty and magic as you seem to be filled with, I would be
able to create poetry that would grab people's attention and blow people's minds as much
as your song is affecting me right this minute." 

There are other
passages in the poem that talk about how much more wonderful the skylark's song is than
any poem ever written by a human being. I've pointed out some of the highlights, but you
can find more