Pierre is a 25﹣year﹣old penguin（企鹅）at the California Academy of Sciences．Due to his old age，he was losing his feathers，which made him feel too cold to swim in the pool．Therefore，biologists at the academy had a wet suit created for this penguin to help him get back in the swimming pool．
Unlike marine（海生的）mammals，which have a layer of blubber（鲸脂）to keep them warm，penguins depend on their waterproof feathers．Without them，Pierre was unwilling to jump into the swimming pool and ended up trembling on the side of the pool while his 19peers played in the water．
"He was cold；he would shake，"said Pam Schaller，a senior biologist．Schaller first tried a heat lamp to keep Pierre warm．Then she got another idea：if wet suits keep humans warm in the cold Pacific，why not make one for Pierre？
Schaller designed the suit，which covered Pierre's body and had small openings for his flippers （鳍）．
"I would walk behind him and look at where there were any gaps，and cut and refit until it looked like it was extremely suitable．"she said．
One concern was that the other penguins would reject Pierre in his new suit，but in fact，they accepted his new look．He swam freely and got along with others well，although he was the only penguin with a black stomach．
Schaller couldn't say for sure whether the wet suit allowed Pierre to recover his fine feathers，but"certainly we were able to keep him comfortable during a period of time that would have been very difficult for him to stay comfortable"．
Pierre will take off his suit after his new feathers grow back．
28．Pierre felt too cold to swim in the pool because of ．
A．having few feathers due to old age
B．not having a layer of blubber
C．having no wet suit
D．others penguins rejecting him
29．The idea of making a wet suit for Pierre came from ．
A．total invention
B．the use of wet suit on humans
C．the use of heat lamp
D．waterproof feathers
30．Schaller followed Pierre in order to see ．
A．whether other penguins would reject him
B．whether the wet suit would keep the feathers from recovering
C．if the wet suit kept warm
D．if anywhere of the wet suit needed to be cut and refit
31．The best title of the passage is ．
A．Unwilling to Swim
B．Old Penguin Getting Bald（秃的）
C．Wet suit for An old Penguin
D．Strange Look of Pierre．