complter solution

features/animal.feature

@@ -1 +1,10 @@
-#Create your feature here
+Feature: Track animals
+  keep the track of name, type and age of every animal
+  Based on the age determine whether the animal is old or not
+
+Scenario: An animal
+  Given Animal is a lion named Leo who is 5 years old
+  Then name of the animal is "Leo"
+  And its type is lion
+  And it is 5 years old
+  And the animal is old

features/step_definitions/animal_steps.rb

@@ -1 +1,21 @@
-#Delete this comment, here is where you should write your step defs
+
+Given (/^Animal is a (.*?) named (.*?) who is (\d+) years old$/) do |type, name, age|
+  @animal = Animal.new(name, type, age.to_i)
+end
+
+Then(/^name of the animal is "(.*?)"$/) do |arg1|
+  #name of the animal is "Leo"
+  expect(@animal.name).to eq arg1
+end
+
+Then(/^its type is (.*?)$/) do |type|
+  expect(@animal.type).to eq type
+end
+
+Then(/^it is (\d+) years old$/) do |age|
+  expect(@animal.age).to eq age.to_i
+end
+
+Then(/^the animal is old$/) do
+  expect(@animal.old?).to be true
+end