Intonation in a language can be compared with a tune in music. It can go up or downwards. In English, the sentence intonation often indicates the mood of the speaker. Different tunes on the same word or phrase can send different messages about the speaker's feelings.

Statement have a falling tone at the end.
WH-question ( who? what? why? when? where? how?) also have a falling tone at the end.
Yes-No questions( question you can answer with "yes" or "no" ) uaually have a raising tone.

Ex:
1. WH-question: How did you spend your vacation? ( falling tone)
2. Statement: I went to Vernice.( falling tone)
3. Yes-No question: Was it expensive?( raising tone)
4. Statement: Yes, very.( falling tone)

In English, important words in a sentence ( usu. nouns, verbs, adjectives, adverbs) are stressed. The unimportant words ( usu. words like the, and, it, is) are not stressed. Normally, the last important word in the sentence has the most tress.

Ex:
1. That's the person who robbed the bank!( falling tone)
2. Do you mean the man with the black pants?( raising tone)
3. No. The woman with the plastic bag.( both of words which are underlined have falling tone)

Twitter