Question

But they are not the only helper animals. There are also guide horses.
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In the second sentence, what is the meaning of 'guide'?
Writeacher
http://www.google.com/search?q=guide+definition&oq=guide+definition&aqs=chrome..69i57.6553j0j7&sourceid=chrome&es_sm=119&ie=UTF-8

Read the 1st verb definition here.