Everyone on the construction site stopped work for a few minutes．The bosstoldthe timekeeper to get all the workersto watch Louie Dumas glue（粘贴）a little GREentortoise sticker（标签）to his safety hat．Lots of workers stick flags on their hardhats，but only special men can wear a green tortoise．The tortoise stickers are given to menwhose lives were saved by the hardhats they wore．Like the tortoise，thesemen werekept alive by their hard shells．
Louie was walking around at lunchtime last week looking for a place to eat in thesunshine，when a big board dropped off the half-finished overpass（立交桥）and hithimon the head．No one knows how the accident happened．But if Louie hadn'tworn ahat，and had been bareheaded，he would have been killed．“I hate this thing，”saidLouie to the onlookers（旁观者）as he tried on his hardhat．“You bake in it or youfreeze in it，but I wouldn't be here without it．”
The boss said，“All of you can learn fromwhat happened to Louie．If you don'twear your hat，we may look for anotherman to fill it．”
90．Louie Dumas glued a little GREen tortoise sticker to his hat because ____．
A．he had been working too slowly
B．he preferred a tortoise sticker toa flag on his hat
C．he was lucky to escape fromdeath
D．his life was saved by the safety hathe was wearing
91．The boss had Louie glue the tortoise sticker to his hat ____．
A．to punish him
B．to praise himfor his high sense of safety
C．as a warning to call the workers'attention to safety
D．to encourage more workers to wear tortoise stickers instead of flags on their hardhats
92．What does“this thing”in the second paragraph refer do？ It refers to ____．
A．the GREen tortoise sticker B．his hardhat
C．wearing a hardhat with a tortoise sticker on it
D．the overpass
key: 90．D 91．C 92．B
