The lines in the poem that best shape the theme that joy can be found in experiencing the natural world are: "Beside the Lake, beneath the trees, /Flittering and dancing in the breeze." "A poet could not but be gay/ In such a jocund company". The first lines "Beside the Lake..." depict a natural scenery and the lines that follow: "A poet could not but be gay...", express that the company of nature makes a poet very happy and feel in good company. The theme is expressed clearly in this set of lines.
Tone in rhetoric is how your writing is conveyed. The type of attitude that you portray. Rhetoric contains many devices such as foreshadowing, flashback, repetition, etc. Tone can be considered one of those devices as it can sway the reader and the writer can use it as what is called a 'Rhetorical strategy' to influence the reader.
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