need help about crack hash

[nhatcto]

you can't use --show to show passwords you have cracked if you haven't cracked any passwords yet.

read the wiki and read the --help output.

yes i am new for start it and i didnt crack any passowrd
all ready now
can u teach me what command run cmd for them working
i want crack email:hash list md5
i read wiki but i cant understand
pls help