Similar parts of a sentence
Sometimes when you write a long emotional piece, and you want to put it all in. You might find yourself chaining several words to make an impact:
The chairwoman was outraged and shocked by what she heard
The chairwoman was bewildered, outraged and shocked by what she heard
The words mean the same, at least in these sentences. If you remove the similars, the sentence will sound stronger:
The chairwoman was shocked by what she heard
But if you really want to highlight the chairwoman's state, it's best to avoid describing her feelings. Better describe what she did. In this next example readers come to a conclusion about the chairwoman's state all by themselves:
When John was done, the chairwoman lit up her microphone to respond. She gasped for breath, but no words came out. Eyes wide open, she gestured as if to find words, but all she could cough out was 'Wh—wh—what?', 'H—h—how?'
You can also use a long series of similar words, but that will look more like a joke:
The chairwoman was shocked, bewildered, outraged, agitated, distressed and perturbed by what she heard
Generally, it's best to avoid pairs of similar words to describe the same thing. One word for one characteristic is usually the best way to go. Unless you know what you are doing and you need these exact two words. But hey, when you know what you are doing, you don't need advice.