posted by Hayley .
1.The chessboard and pieces were placed so that (it, they) could be seen well.
2.The players and the observers looked at (his or her, their) watches.
3.Either the bishop or the knight will lose (its, their) powerful position.
4.Neither the players nor the observers expressed (his or her, their0 opinions.
5.A marble chess set or a wooden chess set will retain (its, their) value.
All right, except for # 5.