In the poem "Tintern Abbey," show how Wordsworth can be called a romantic poet?

Romantic poetry is defined by what William Wordsworth and
a few other writers wrote.  Wordsworth is a romantic poet, so "Tintern Abbey" is a
romantic poem.  He defines romantic poetry, not the other way around.  In other words,
anything you find in the poem is a characteristic of romantic poetry, since Wordsworth
defines it. 

"Tintern Abbey" demonstrates a love for
nature, of course.  Nature is something to study and contemplate and learn from.  It can
lead one to an experience of the sublime, a feeling of awe and a feeling of oneness with
nature; a transcendent experience beyond human reason.  Contemplation of nature makes
one a better human being. 

Other elements that you can
point to exist in the poem, but perhaps the most significant is Wordsworth's revelation
of his writing process.  The poem reveals how Wordsworth creates poetry.  He experiences
nature, spends time contemplating it, then writes about it.  He experiences, then later
recollects and writes in tranquility.  That's what happens in the poem:  it's very much
about the first time the speaker visited the area, not the
second.