Here is an accent reduction tip that is REALLY important for non native speakers to understand.
When Americans are speaking they do not stress every word in a sentence equally!
This means that in order to reduce your accent you need to learn about how American English speakers use focus words and sentence stress.
American English speakers stress the CONTENT and FOCUS words in a sentence or phrase. That’s because CONTENT and FOCUS words are integral to the meaning of a sentence.
They reduce the sounds of function words in a sentence because while these words hold a sentence together, they are not key to meaning.
In spoken American English each sentence or phrase contains:
A Focus word-the most important word
Content words-very important for meaning
Function words-not important for meaning
Content Words and Focus Words
The most important words in English sentences are CONTENT words and FOCUS words. Content and focus words are pronounced louder and with a higher pitch than the other words in a sentence.
CONTENT words are usually nouns, main verbs, adjectives, adverbs, question words, negatives and numbers.
The FOCUS word is usually the last content word in a phrase or sentence.
In the sentences below notice the CONTENT and FOCUS words. Americans will pronounce these words with more emphasis than the other less important words.
1. SUSAN is HAPPY in her new POSITION.
2. She conducts her MEETINGS in the BOARDROOM.
In longer sentences, there is a focus word in each phrase or thought group.
1. If you PLAN to become a DOCTOR, you need to study ANATOMY.
Function Words
The unstressed words are called function words. Function words are important to the grammatical structure of a sentence but they don’t convey much meaning. Function words are pronounced quickly with a low pitch so when Americans pronounce them they are difficult to hear.
Stressing Function Words
In certain situations, speakers may choose to stress a function word rather than a content or focus word. For example, when someone gives you a choice and you want to choose both items your should stress the structure word. 
Mother: Would you like CAKE or ICE CREAM?
Child: I’d like cake AND ice cream!
Using content, focus and function words correctly is important because the emphasis and reductions create a speech rhythm that is familiar to Americans listeners. If you don’t use sentence stress correctly your speech will sound flat and uninteresting.
You will learn how to apply sentence stress using content, focus and function words when you sign up for my accent reduction classes or coaching program.
Not ready for coaching? You can get started reducing your accent right away by using my accent reduction book for the iPad . While not as effective as live training, this audio course will teach you the rules you need to know to reduce your accent.