i.e. When she <b>sang</b> her song, she sat down.<br/> When she <b>had sung</b> her song, she sat down.<br/><br/>For the first sentence,<br/><u>After she finished singing her song and she sat down.</u> (just showing the sequence, though I'm not quite sure about this.)<br/><br/>and the second sentence is paraphrased,<br/><u>She sang her song while sitting down. </u>(also I'm not sure whether it is the right interpretation.)<br/><br/>Am I get it right?