diff --git a/test/test-traversal-1.rkt b/test/test-traversal-1.rkt
index bc0216f..aa9c606 100644
--- a/test/test-traversal-1.rkt
+++ b/test/test-traversal-1.rkt
@@ -13,6 +13,8 @@
 (define-fold f₆ t₆ (List Null (Pairof Null Null) Null) String)
 (define-fold f₇ t₇ (Listof String) String)
 (define-fold f₈ t₈ (List String Foo (Listof String)) String)
+(define-fold f₉ t₉ (List (Listof String) Foo (Listof String)) (Listof String))
+(define-fold f₁₀ t₁₀ (List String Foo (Listof String)) (Listof String))
 
 (define (string->symbol+acc [x : String] [acc : Integer])
   (values (string->symbol x) (add1 acc)))
@@ -61,4 +63,32 @@
                                                        0)
                       : (Values (List Symbol (Listof String) (Listof Symbol))
                                 Integer)
-                      '(abc ("def" "ghi") (jkl mno)) 3)
\ No newline at end of file
+                      '(abc ("def" "ghi") (jkl mno)) 3)
+
+(check-equal?-values: ((f₉ (make-predicate (Listof String))
+                           (λ ([l : (Listof String)] [acc : Integer])
+                             (values (map string->symbol l)
+                                     (add1 acc))))
+                       '(("a" "b" "c")
+                         ("def" "ghi")
+                         ("jkl" "mno"))
+                       0)
+                      : (Values (List (Listof Symbol)
+                                      (Listof String)
+                                      (Listof Symbol))
+                                Integer)
+                      '((a b c) ("def" "ghi") (jkl mno)) 2)
+
+(check-equal?-values: ((f₁₀ (make-predicate (Listof String))
+                           (λ ([l : (Listof String)] [acc : Integer])
+                             (values (map string->symbol l)
+                                     (add1 acc))))
+                       '("abc"
+                         ("def" "ghi")
+                         ("jkl" "mno"))
+                       0)
+                      : (Values (List String
+                                      (Listof String)
+                                      (Listof Symbol))
+                                Integer)
+                      '("abc" ("def" "ghi") (jkl mno)) 1)
\ No newline at end of file