Specific use of Linux man command

Usage: man [OPTION...] [section] man page...
 -a, --all find all matching manual pages -d, --debug output debugging information -D, --default reset all options to default values ​​--warnings[=WARNING] turn on groff warnings -f, --whatis equivalent to whatis
 -h displays the syntax and parameter description of man and exits the program after execution.
 -k, --apropos is equivalent to apropos and will search the whatis database for fuzzy search keywords -S, -s, --sections=list uses a colon-separated list of sections -t, --troff uses groff to typeset manual pages -w, --where, --path, --location
               Output the physical location of the manual page -W, --where-cat, --location-cat
               Output the physical location of the cat file -c, --catman Used by catman to correct outdated cat
               Page reformatting -C, --config-file=file Use this user configuration file -K, --global-apropos search for text in all pages
 -M, --manpath=path Set the search path for manual pages to 'path'
 -?, --help give this help list
   --usage give a short usage message
 -V, --version print program version
 -R, --recode=encode output source page encoded in ENCODING
 Find the man page:
 -L, --locale=LOCAL Define the locale to use for this manual page search -m, --systems=SYSTEM use manual pages from other systems
 -e, --extension=extended Limit the search to manual pages with extension type "extended" -i, --ignore-case Do not distinguish between uppercase and lowercase letters when searching manual pages (default)
 -I, --match-case Match uppercase and lowercase letters when searching man pages.

   --regex show all pages matching regex
   --wildcard show all pages matching wildcard

   --names-only makes --regex and --wildcard match page names only,
               not descriptions 

-S section-list The list is a colon-delimited list of manual pages to search. This option overrides the MANSECT environment variable.
  Some instructions or procedures may have more than one topic, which are located in different sections. So, to view later sections, you can specify here the order in which man should search for sections. The specific segment divisions are as follows:
  Section 1: User commands Section 2: System calls Section 3: Library calls Section 4: Devices Section 5: File formats Section 6: Games Section 7: Miscellaneous Section 8: System commands Section 9: Kernel internal commands Section n: Tcl or Tk commands 

[deng@localhost ~]$ whatis cd 
cd (1) - GNU Bourne-Again SHell (GNU Command Interpreter "Bourne II")
cd (3tcl) - change the working directorycd (1p) - change the working directory
[deng@localhost ~]$

View the bash command, and then search through /cd [deng@localhost ~]$ man 1 cd 
Use the following command to directly view the help information of cd.
[deng@localhost ~]$ man 1p cd

[deng@localhost ~]$ man 2 read

[deng@localhost ~]$ man 3 sleep

[deng@localhost ~]$ man 4 tty

[deng@localhost ~]$ man 5 passwd

[deng@localhost ~]$ man 8 fdisk