1) The craven poltroon fled from the battlefield, leaving his comrades behind.
2) The poltroon was so cowardly that he would not even stand up for himself when he was being bullied.
3) The poltroon was too afraid to speak his mind, even though he knew that he was right.
4) The poltroon was so timid that he would not even go outside on a dark night.
5) The poltroon was so faint-hearted that he would not even cross a bridge over a river.