Machine learning is a way of teaching computers to do tasks.In the past，to do something，computers relied on detailed，step-by-step instructions written by a person.But with machine learning，computers pick up new skills on their own，using examples or experience.（1）

C

C

AI is the ability of a machine to think or learn like a person.
   There are a few types of machine learning.The most common is supervised（監(jiān)督）learnjye.aig.In this method，a computer is fed lots of labeled training data.（2）

A

A

Each photo might be labeled with the dog's breed（品種）.By studying those photos，the computer learns what each breed looks like.Then，the computer can pick out dog breeds in new，unlabeled photos.The more data the computer studies，the better it gets at its task.
  （3）

E

E

Using this type of learning is sort of like training your dog to do a trick.The computer learns to achieve some goal by interacting with its environment.When the computer makes a choice that brings it closer to its goal，it gets a virtual reward.（4）

B

B

This type of machine learning has helped computers master difficult games like Go and Star Craft II.
   Machine learning has helped create technology all around us.It powers language translators and search engines.When your streaming （services recommend new shows you might like，that's machine learning at work.Machine learning systems also organize posts in social media feeds.
   They even help diagnose diseases.（5）

F

F

A.For instance，it may look at many photos of dogs.
B.Through many times，the computer learns to make better choices.
C.This makes machine learning a powerful form of artificial intelligence.
D.Its systems power many kinds of machines-from smartphones to robots.
E.Another important kind of machine learning is reinforcement learning.
F.In many ways，the problem-solving power of machine learning is changing the world.
G.A computer program allows a computer to search for information on the Internet.