我的朋友比尔喜欢在闲暇时观察鸟类。几年前,比尔买了一幢新房子,附近草木茂盛。入住后的第一个周末,他就在后院装了个喂鸟器。可当天日暮时分,一群松鼠便弄倒了喂鸟器,吃掉了里面的食物,把小鸟吓得四散飞去。在接下来的两周里,比尔绞尽脑汁想出各种办法让松鼠远离喂鸟器,就差? My friend Bill likes to watch birds in his spare time. A few years ago, Bill bought a new house, surrounded by lush vegetation. On the first weekend after his arrival, he installed a bird feeder in the backyard. At the end of the day, a group of squirrels set up the bird feeders, ate the food inside, and scared the birds away. In the next two weeks, Bill racked his brains to come up with a variety of ways to keep squirrels away from bird feeders.