id=WWMpdHUhQ_QC&printsec=frontcover&dq=discourse+markers+in+english&hl=en&ei=hHlUTJX-N8L78AbJ__W1DA&sa=X&oi=book_result&ct=result&resnum=4&ved=0CEAQ6AEwAw . It is a specialized academic subject, not something you will find in basic grammar texts. If you have particular questions, you can post them here.
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