Rules for Sentence Stress in English

The basic rules of sentence stress are:

@content words are stressed
@structure words are unstressed
@the time between stressed words is always the same

The following exemples can help you decide which words are content words and which words are

structure words:

Content words - stressed

Words carrying the meaning

Example
main verbs:========SELL, GIVE, EMPLOY
nouns:============CAR, MUSIC, MARY
adjectives:=========RED, BIG, INTERESTING
adverbs:==========QUICKLY, LOUDLY, NEVER
negative auxiliaries:==DON'T, AREN'T, CAN'T


Structure words - unstressed

Words for correct grammar

Example

pronouns========he, we, they
prepositions======on, at, into
articles=========a, an, the
conjunctions=====and, but, because
auxiliary verbs===do, be, have, can, must

Exceptions

The above rules are for for what is called "neutral" or normal stress. But sometimes we can stress a word that would normally be only a structure word, for example to correct information. Look at the following dialogue:

"They've been to Mongolia, haven't they?""No, THEY haven't, but WE have.

Note also that when "be" is used as a main verb, it is usually unstressed (even though in this case it is a content word).