Sonnet: a lyric poem consisting of fourteen lines. In English, generally the two basic kinds of sonnets are the Italian or Petrarchan sonnet and the Shakespearean or Elizabethan sonnet. The Italian/Petrarchan sonnet is named after Petrarch, an Italian Renaissance poet. The Petrarchan sonnet consists of an octave (eight lines) and a sestet (six lines). The Shakespearean sonnet consists of three quatrains (four lines each) and a concluding couplet (two lines). The Petrarian sonnet tends to divide the thought into two parts; the Shakespearean, into four.
Structure: framework of a work of literature; the organization or over-all design of a work. The structure of a play may fall into logical divisions and also a mechanical division of acts and scenes. Groups of stories may be set in a larger structure or frame, like The Canterbury Tales, The Decameron, or The Arabian Tales.
Style: manner of expression; how a speaker or writer says what he says. Notice the difference in style of the opening paragraphs of Hemingway's A Farewell to Arms and Mark Twain's The Adventures of Huckleberry Finn:
In the late summer of that year we lived in a house in a village that looked across the river and the plain to the mountains. In the bed of the river there were pebbles and boulders, dry and white in the sun, and the water was clear and swiftly moving and blue in the channels. Troops went by the house and down the road and the dust they raised powdered the leaves of the trees. The trunks of the trees too were dusty and the leaves fell early that year and we saw the troops marching along the road and the dust rising and leaves, stirred by the breeze, falling and the soldiers marching and afterward the road bare and white except for the leaves.
A Farewell to Arms
You don't know about me without you have read a book by the name of The Adventures of Tom Sawyer; but that ain't no matter. That book was made by Mr. Mark Twain, and he told the truth, mainly. There was things which he stretched, but mainly he told the truth.
The Adventures of Huckleberry Finn
Symbol: in general terms, anything that stands for something else. Obvious examples are flags, which symbolize a nation; the cross is a symbol for Christianity; Uncle Sam a symbol for the United States. In literature, a symbol is expected to have significance. Keats starts his ode with a real nightingale, but quickly it becomes a symbol, standing for a life of pure, unmixed joy; then before the end of the poem it becomes only a bird again.
Tone: the writer's attitude toward the material and/or readers. Tone may be playful, formal, intimate, angry, serious, ironic, outraged, baffled, tender, serene, depressed, etc.
Theme: (1) the abstract concept explored in a literary work; (2) frequently recurring ideas, such as enjoy-life while-you-can; (3) repetition of a meaningful element in a work, such as references to sight, vision, and blindness in Oedipus Rex. Sometimes the theme is also called the motif. Themes in Hamlet include the nature of filial duty and the dilemma of the idealist in a non-ideal situation. A theme in Keats's "Ode to a Nightingale" is the difficulty of correlating the ideal and the real.