diff --git a/compiler/erg_compiler/context/inquire.rs b/compiler/erg_compiler/context/inquire.rs
index 8cf36caa..ad51dcbb 100644
--- a/compiler/erg_compiler/context/inquire.rs
+++ b/compiler/erg_compiler/context/inquire.rs
@@ -1019,6 +1019,20 @@ impl Context {
                     }
                 } else {
                     // pos_args.len() < non_default_params_len
+                    let mut params = non_default_params.chain(subr.default_params.iter());
+                    for pos_arg in pos_args.iter() {
+                        if let Err(mut es) = self.substitute_pos_arg(
+                            &callee,
+                            attr_name,
+                            &pos_arg.expr,
+                            nth,
+                            params.next().unwrap(),
+                            &mut passed_params,
+                        ) {
+                            errs.append(&mut es);
+                        }
+                        nth += 1;
+                    }
                     for kw_arg in kw_args.iter() {
                         if let Err(mut es) = self.substitute_kw_arg(
                             &callee,
@@ -1032,7 +1046,7 @@ impl Context {
                         }
                         nth += 1;
                     }
-                    let missing_len = non_default_params_len - pos_args.len() - passed_params.len();
+                    let missing_len = params_len - passed_params.len();
                     if missing_len > 0 {
                         let missing_params = subr
                             .non_default_params
@@ -1040,7 +1054,7 @@ impl Context {
                             .rev()
                             .take(missing_len)
                             .rev()
-                            .map(|pt| pt.name().cloned().unwrap_or(Str::ever("")))
+                            .map(|pt| pt.name().cloned().unwrap_or(Str::ever("_")))
                             .filter(|pt| !passed_params.contains(pt))
                             .collect();
                         return Err(TyCheckErrors::from(TyCheckError::args_missing_error(
@@ -1173,6 +1187,20 @@ impl Context {
     ) -> TyCheckResult<()> {
         let arg_t = arg.ref_t();
         let param_t = &param.typ();
+        if let Some(name) = param.name() {
+            if passed_params.contains(name) {
+                return Err(TyCheckErrors::from(TyCheckError::multiple_args_error(
+                    self.cfg.input.clone(),
+                    line!() as usize,
+                    callee.loc(),
+                    &callee.to_string(),
+                    self.caused_by(),
+                    name,
+                )));
+            } else {
+                passed_params.insert(name.clone());
+            }
+        }
         self.sub_unify(arg_t, param_t, arg.loc(), param.name())
             .map_err(|errs| {
                 log!(err "semi-unification failed with {callee}\n{arg_t} !<: {param_t}");
@@ -1201,20 +1229,6 @@ impl Context {
                         .collect(),
                 )
             })?;
-        if let Some(name) = param.name() {
-            if passed_params.contains(name) {
-                return Err(TyCheckErrors::from(TyCheckError::multiple_args_error(
-                    self.cfg.input.clone(),
-                    line!() as usize,
-                    callee.loc(),
-                    &callee.to_string(),
-                    self.caused_by(),
-                    name,
-                )));
-            } else {
-                passed_params.insert(name.clone());
-            }
-        }
         Ok(())
     }
 
@@ -1287,6 +1301,7 @@ impl Context {
             .chain(subr_ty.default_params.iter())
             .find(|pt| pt.name().unwrap() == kw_name)
         {
+            passed_params.insert(kw_name.clone());
             self.sub_unify(arg_t, pt.typ(), arg.loc(), Some(kw_name))
                 .map_err(|errs| {
                     log!(err "semi-unification failed with {callee}\n{arg_t} !<: {}", pt.typ());
diff --git a/tests/should_err/args.er b/tests/should_err/args.er
new file mode 100644
index 00000000..e0bc39bc
--- /dev/null
+++ b/tests/should_err/args.er
@@ -0,0 +1,18 @@
+print! sep:="" # OK
+print! 1, "", sep:="" # OK
+print! end:="", sep:="" # OK
+print! 1, end:="", sep:="" # OK
+
+add x: Int!, y: Int = x - y
+print! add !1, 1 # OK
+print! add x:=!1, y:=2 # OK
+print! add y:=1, x:=!2 # OK
+print! add !1, y:=1 # OK
+print! add x:=!1, y:="" # ERR, the type of y is wrong
+print! add x:=!1, y:=2, z:=1 # ERR, z is unexpected
+print! add x:=!1, y:=2, x:=!2 # ERR, x is passed twice
+print! add x:=!1, y:=2, x:=!2, z:=1 # ERR, x is passed twice, z is unexpected
+print! add "", y:=1 # ERR, the type of x is wrong
+print! add !1, 1, y:=1 # ERR, too many args
+print! add "", y:=1, x:=1 # ERR, the type of x is wrong, x is passed twice (or args are too many)
+print! add "", y:="" # ERR, the types of x, y are wrong
diff --git a/tests/test.rs b/tests/test.rs
index 6abe341c..4cc06ea2 100644
--- a/tests/test.rs
+++ b/tests/test.rs
@@ -124,6 +124,11 @@ fn exec_addition_err() -> Result<(), ()> {
     expect_failure("tests/should_err/addition.er", 1)
 }
 
+#[test]
+fn exec_args() -> Result<(), ()> {
+    expect_failure("tests/should_err/args.er", 10)
+}
+
 #[test]
 fn exec_invalid_param() -> Result<(), ()> {
     expect_failure("tests/should_err/invalid_param.er", 3)