There are no steel-riveted rules of emphasis. It is not always possible to designate which word must, and which must not be emphasized. One speaker will put one interpretation on a speech, another speaker will use different emphasis to bring out a different interpretation. No one can say that one interpretation is right and the other wrong. This principle must be borne in mind in all our marked exercises. Here your own intelligence must guide—and greatly to your profit.
Here is another sentence to demonstrate emphasis and the changes that can be made.
I intended to buy a house this Spring (even if you did not).
I INTENDED to buy a house this Spring (but something prevented).
I intended to BUY a house this Spring (instead of renting as heretofore).
I intended to buy a HOUSE this Spring (and not an automobile).
I intended to buy a house THIS Spring (instead of next Spring).
I intended to buy a house this SPRING (instead of in the Autumn).
Strongly emphasizing a single word has a tendency to suggest its antithesis. Notice how the meaning changes by merely putting the emphasis on different words in the sentence. The parenthetical expressions would really not be needed to supplement the emphatic words.
From all this we may deduce this important principle: EMPHASIS is a matter of CONTRAST and COMPARISON.
Sometimes, for big emphasis, it is advisable to lay stress on every single syllable in a word, as absolutely in the following sentence:
I ab-so-lute-ly refuse to grant your demand.