Rules for Sentence Stress in English
The basic rules of sentence stress are:
The following tables can help you decide which words are content words and which words are structure words:
Content words - stressed
Structure words - unstressed
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:
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).