diff --git a/idioms/ffi-passing-strings.md b/idioms/ffi-passing-strings.md
index e745772..18de5c8 100644
--- a/idioms/ffi-passing-strings.md
+++ b/idioms/ffi-passing-strings.md
@@ -42,7 +42,7 @@ pub mod unsafe_module {
 
         unsafe {
             // SAFETY: calling an FFI whose documentation says the pointer is
-            // const, so no modificationshould occur
+            // const, so no modification should occur
             seterr(c_err.as_ptr());
         }