阅读下面材料，在空白处填入适当的内容(1个单词)或括号内单词的正确形式。
The greyhound is a dog with a long neck and head，and small ears.They come in a variety 56. colors including black，red and white.They have long and powerful legs and small feet 57. help them move fast.In fact，they are the fastest dogs around.Young 58. (health) greyhounds can run up to 72km per hour.They usually live for about 15 years or sometimes more.
In the past，greyhounds 59. (train) to hunt and were very good hunting dogs.They haven’t given 60. hunting but nowadays they also have another purpose.Greyhounds have been trained by professionals for many years 61. (race)，and many people go to the racetracks to watch them run.
Like most athletes，greyhounds have relatively short careers.When they 62. (run) their last race，they’re still quite young and have the potential to live long.But these 63. (retire) racers need good homes.
64． (fortunate)，greyhounds are friendly and gentle with children.Families who have adopted greyhounds agree that a(n) 65. (good) pet cannot be found!
56．答案 of
解析 考查介词。a variety of意为“各种各样的”，为固定搭配。
57．答案 that/which
解析 考查关系代词。所填词引导定语从句，修饰先行词long and powerful legs and small feet，且在从句中作主语，故填that/which。
58．答案 healthy
解析 考查形容词。修饰名词greyhounds，故填形容词healthy。
59．答案 were trained
解析 考查时态和语态。由In the past可知，此处用一般过去时；且greyhounds与train之间是被动关系，故填were trained。
60．答案 up
解析 考查副词。give up意为“放弃”，为固定搭配。
61．答案 to race
解析 考查非谓语动词。训练灰狗的目的是让其参加比赛，动词不定式短语作目的状语，故填to race。
62．答案 have run
解析 考查时态。句意为“当它们完成最后一次比赛时”，表示到现在动作已经完成，故从句用现在完成时。
63．答案 retired
解析 考查形容词。所填词在句中作定语，故用形容词，retired意为“退休的”。
64．答案 Fortunately
解析 考查副词。所填词修饰整个句子，意为“幸运地”，故填Fortunately。
65．答案 better
解析 考查比较级。由cannot be found可知，此处用比较级，表示“比它更好的宠物”，故填better。
The greyhound is a dog with a long neck and head，and small ears.They come in a variety 56. colors including black，red and white.They have long and powerful legs and small feet 57. help them move fast.In fact，they are the fastest dogs around.Young 58. (health) greyhounds can run up to 72km per hour.They usually live for about 15 years or sometimes more.
In the past，greyhounds 59. (train) to hunt and were very good hunting dogs.They haven’t given 60. hunting but nowadays they also have another purpose.Greyhounds have been trained by professionals for many years 61. (race)，and many people go to the racetracks to watch them run.
Like most athletes，greyhounds have relatively short careers.When they 62. (run) their last race，they’re still quite young and have the potential to live long.But these 63. (retire) racers need good homes.
64． (fortunate)，greyhounds are friendly and gentle with children.Families who have adopted greyhounds agree that a(n) 65. (good) pet cannot be found!
56．答案 of
解析 考查介词。a variety of意为“各种各样的”，为固定搭配。
57．答案 that/which
解析 考查关系代词。所填词引导定语从句，修饰先行词long and powerful legs and small feet，且在从句中作主语，故填that/which。
58．答案 healthy
解析 考查形容词。修饰名词greyhounds，故填形容词healthy。
59．答案 were trained
解析 考查时态和语态。由In the past可知，此处用一般过去时；且greyhounds与train之间是被动关系，故填were trained。
60．答案 up
解析 考查副词。give up意为“放弃”，为固定搭配。
61．答案 to race
解析 考查非谓语动词。训练灰狗的目的是让其参加比赛，动词不定式短语作目的状语，故填to race。
62．答案 have run
解析 考查时态。句意为“当它们完成最后一次比赛时”，表示到现在动作已经完成，故从句用现在完成时。
63．答案 retired
解析 考查形容词。所填词在句中作定语，故用形容词，retired意为“退休的”。
64．答案 Fortunately
解析 考查副词。所填词修饰整个句子，意为“幸运地”，故填Fortunately。
65．答案 better
解析 考查比较级。由cannot be found可知，此处用比较级，表示“比它更好的宠物”，故填better。
