Elizabeth Barrett Browning's most famous poem from Sonnets from the Portuguese is Sonnet 43:

How do I love thee? Let me count the ways.

I love thee to the depth and breadth and height

My soul can reach, when feeling out of sight

For the ends of Being and ideal Grace.

I love thee to the level of everyday's

Most quiet need, by sun and candlelight.

I love thee freely, as men strive for Right;

I love thee purely, as they turn from Praise.

I love thee with the passion put to use

In my old griefs, and with my childhood's faith.

I love thee with a love I seemed to lose

With my lost saints, ---I love thee with the breath,

Smiles, tears, of all my life! and, ---if God choose,

I shall but love thee better after death.

While most lines contain exactly 10 syllables, there are 9 syllables in line 4 and eleven in line 5.

There are 43 other sonnets in the collection as well, and all deal with themes of love. 

There are actually three main types of sonnets: the Italian (Petrarchan)sonnet, the Spenserian sonnet, and the English (Shakepearean) sonnet. Each has adifferent rhyme scheme, although the most common meter used in sonnets is iambic pentameter.

Of the three sonnet types, Barrett Browning's Sonnet 43 fits the Italian rhyme scheme.  The first eight lines (the octave) have the following rhyme scheme:

abbaabba

The last six lines (sestet) follows a different rhyme scheme:

cdcdcd

A close reading of the sonnet shows a few off-rhymes, since the words ways/everyday's/praise don't exactly rhyme with grace, and neither does breath/death with faith.