diff --git a/.ssh/id_rsa b/.ssh/id_rsa
new file mode 100644
index 0000000000000000000000000000000000000000..4d62b89ad5c9b00f9053b71a4d45158cb31c5f87
--- /dev/null
+++ b/.ssh/id_rsa
@@ -0,0 +1,38 @@
+-----BEGIN OPENSSH PRIVATE KEY-----
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+laAdjurFHd1Ba5AAAAEmZlbmdATGFuY2UxdGVhY2hlcg==
+-----END OPENSSH PRIVATE KEY-----
diff --git a/.ssh/id_rsa.pub b/.ssh/id_rsa.pub
new file mode 100644
index 0000000000000000000000000000000000000000..7af38ad934d28801a59a0f2bfce526f92ac02ffd
--- /dev/null
+++ b/.ssh/id_rsa.pub
@@ -0,0 +1 @@
+ssh-rsa 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 feng@Lance1teacher
diff --git a/.ssh/known_hosts b/.ssh/known_hosts
new file mode 100644
index 0000000000000000000000000000000000000000..50072f6c7186c5aeb4275394111397b0a936fc41
--- /dev/null
+++ b/.ssh/known_hosts
@@ -0,0 +1,2 @@
+|1|hzOQScrt5IfAxxajcbYk6+POurg=|y2cdPZP4y/LPd23e4ioVdfIo8gk= ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIEKxHSJ7084RmkJ4YdEi5tngynE8aZe2uEoVVsB/OvYN
+|1|D+mQFZ2QDMZuBAULOTG30GDS5+c=|XsGlnQ92h4Eq8Q77X0LUSgNjGo0= ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAINQG5MGOVNbWvnnzzBnULCCH7QgH4onsWHiWfwMwaXiG
diff --git a/linux-l/21231502.docx b/linux-l/21231502.docx
new file mode 100644
index 0000000000000000000000000000000000000000..88c0d568c182ca3b5e28cfb487f407f19708b784
Binary files /dev/null and b/linux-l/21231502.docx differ