diff --git a/src/kernel/mod.rs b/src/kernel/mod.rs
index c87b037..df9b60d 100644
--- a/src/kernel/mod.rs
+++ b/src/kernel/mod.rs
@@ -2,6 +2,6 @@ pub mod process;
 pub mod thread;
 pub mod mgerror;
 pub mod system;
-mod synch;
+pub mod synch;
 mod thread_manager;
 pub mod exception;
\ No newline at end of file
diff --git a/src/kernel/synch.rs b/src/kernel/synch.rs
index 6fe22e3..f3682f3 100644
--- a/src/kernel/synch.rs
+++ b/src/kernel/synch.rs
@@ -1,5 +1,4 @@
 use crate::utility::list::List;
-use crate::utility::objaddr::*;
 use crate::kernel::thread::Thread;
 use crate::simulator::interrupt::InterruptStatus::InterruptOff;
 use crate::simulator::machine::Machine;
@@ -17,8 +16,6 @@ pub struct Semaphore {
 
 }
 
-impl SynchObj for Semaphore {}
-
 impl Semaphore {
 
     ///     Initializes a semaphore, so that it can be used for synchronization.
@@ -92,8 +89,6 @@ pub struct Lock{
 
 }
 
-impl SynchObj for Lock {}
-
 impl Lock {
 
     ///    Initialize a Lock, so that it can be used for synchronization.
@@ -198,8 +193,6 @@ pub struct Condition{
     
 }
 
-impl SynchObj for Condition {}
-
 impl Condition {
 
     /// Initializes a Condition, so that it can be used for synchronization.