短文填空。根据短文内容，选择方框中所给的单词填空，使文章完整通顺。注意：1、不用改变形式；2、每词限使用一次。
either, make, signs, them, best, provide, who, sure, prevents, others
If you visit the animal shelter (收容所) in Salinas, California, you’ll see huge signs that have a picture of a dog and a cat on them. These ____ are put in front of the shelter to catch people’s attention. The signs ____ people interested in the shelter and encouraged them to visit it and maybe even take a cat or a dog into their homes.
Each year, the Salinas shelter accepts thousands of dogs and cats. The animals are____ lost ones or are left by people who can't take care of____ . Of all the animals, some of them are taken into new homes. Some____ are moved to other shelters. And, unluckily, some cannot be saved because they are too sick or are thought to be dangerous.
Animal shelters ____ food, medicine, and safe places for animals. But they are not the ____ homes. The animals stay in small cages (笼子). The people____ work at shelters do their best to care for the animals, but the animals do not always get the attention or exercise they need.
To prevent animals from becoming homeless, pet owners should take good care of their pets. Most pet doctors also suggest people make ____ their pets have a special surgery ( 外科手术). It____ animals from having more babies. And that reduces（减少）the number of homeless animals.
