Which two sentences best express the main ideas of the passage?

The two sentences that Express the main idea of the passage is the topic sentence and the thesis

Thesis statement: By using imagery and diction, both William Wordsworth and John Muir describes how nature have the powerful impact to bring happiness in a person's life.

Explanation:

Bridge: John Muir's essay 'Calypso Borealis' and William Wordsworth's poem 'I Wandered Lonely as a Cloud' engages with nature and illustrates the power and beauty of nature. Muir's essay is a perfect example of naturalism where he accurately describes a flower name Calypso Borealis and draws attention to natures beauty. Similarly, Wordsworth depicts how he have encountered a field of flowers and how this in turn helped him to brighten up his mood.

Both William Wordsworth and John Muir have made use of imagery, positive tone, and connotation to call attention to the beauty of nature.