In the United States , many people use the English system for measuring . While some people use the metric system , our idioms and expressions often stick with measurement words from the English system . Today , we talk about expressions using the word mile . And we have miles and miles of them ! That means we have a lot . For example , if you can run a mile a minute , you can run very fast . So , we can use the expression “a mile a minute ” to describe people who do things very quickly . For example , Sarah was very excited about her trip ! When she told us about it , she talked a mile a minute . We could barely follow what she was saying ! Here is another example . His brain seems to work a mile a minute . Now , when we talk about running a race , we use both kilometers and miles . However , when we use the expression “go the extra mile ,” we only use mile . If you run a race that is 10 miles long and you run 11 miles , you have run farther than others and farther than needed . So , when we go the extra mile , we do more than is asked of us . We do this to prove we are hardworking or dedicated to something . For example , many friends were only supposed to collect used books for a literary organization . But Tory went the extra mile ; she delivered the books to needy families in the community . A mile is equal to 1.6 kilometers . That is far enough away that you cannot see , smell , or notice something . Well , at least it should be . So , if we say , “I could see that from a mile away ,” it means something is very noticeable . For example , I can spot a liar from a mile away . That means I am very good at detecting people who do not tell the truth . Even if they are a mile from me , I can tell . If a scent is very strong , you could say you smell it from a mile away . I don't know what cologne that man was wearing , but I could smell it a mile away . To be a million miles away is even farther . We often use that expression to mean lost in thought . If I am a million miles away , I seem very far away from those around me . We can also use it to compare things . For example , her goals for her future and her parent's goals for her future were a million miles apart . The two goals had nothing in common . Our last expression describes people who are selfish and greedy . They always want more . If you give some people a little of something , they will often take a lot . I knew a woman who was like that . Every time I "gave her an inch , she took a mile ." She always wanted more from the people around her .