What idea is the focus of the second two stanzas

2 line stanzas are called Couplets. Couplets usually rhyme. A stanza in poetry is a group of lines usually separated by a blank line. Stanzas of 2 lines are called Couplets from the Old French word cople meaning two.

Explanation:

pitch- the definition of pitch is as follows:

"the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone."