diff --git a/task1/CodegenImpl.java b/task1/CodegenImpl.java
index 2098b2b..45539fa 100644
--- a/task1/CodegenImpl.java
+++ b/task1/CodegenImpl.java
@@ -54,7 +54,9 @@ public class CodegenImpl implements Codegen {
 			+ "mv s1,a0\n"
 			+ compileExp(b.r)
 			+ "mv t1,a0\n"
-			+ compileExpBinop(b.binop);
+			+ compileExpBinop(b.binop)
+			+ "lw s1,(sp)\n"
+			+ "addi sp,sp,4\n";
 		} else if (e instanceof Variable) {
 			int offset = ((Variable) e).x - 1;
 			
diff --git a/task2/CodegenImpl.java b/task2/CodegenImpl.java
index 2098b2b..45539fa 100644
--- a/task2/CodegenImpl.java
+++ b/task2/CodegenImpl.java
@@ -54,7 +54,9 @@ public class CodegenImpl implements Codegen {
 			+ "mv s1,a0\n"
 			+ compileExp(b.r)
 			+ "mv t1,a0\n"
-			+ compileExpBinop(b.binop);
+			+ compileExpBinop(b.binop)
+			+ "lw s1,(sp)\n"
+			+ "addi sp,sp,4\n";
 		} else if (e instanceof Variable) {
 			int offset = ((Variable) e).x - 1;
 			
diff --git a/task3/CodegenImpl.java b/task3/CodegenImpl.java
index 2098b2b..45539fa 100644
--- a/task3/CodegenImpl.java
+++ b/task3/CodegenImpl.java
@@ -54,7 +54,9 @@ public class CodegenImpl implements Codegen {
 			+ "mv s1,a0\n"
 			+ compileExp(b.r)
 			+ "mv t1,a0\n"
-			+ compileExpBinop(b.binop);
+			+ compileExpBinop(b.binop)
+			+ "lw s1,(sp)\n"
+			+ "addi sp,sp,4\n";
 		} else if (e instanceof Variable) {
 			int offset = ((Variable) e).x - 1;