Use the following two groups of sentences as examples to illustrate how to use super-ordinates and subordinates. （a） There was a fine rocking-chair that his father used to sit in a desk where he wrote letters, a nest of small tables and a dark bookcase. Now all this furniture was to be sold, and with it his own past. （b） 1） Trees surround the water near our summer place. 　2） Old elms surround the lake near our summer cabin.