Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Definitions of special expressions used for stop word lists. An inner front word is the word preceding a left parenthesis, an inner first word is the first inner word, and an outer first word is the first outer word. This figure shows an example that an outer and an inner consist of three and two words, respectively.
