Update learn.php

learn.php

@@ -111,6 +111,13 @@ async function check() {
 
 loadWord();
 
+document.getElementById('answer').addEventListener('keydown', function (e) {
+    if (e.key === 'Enter') {
+        e.preventDefault();
+        check();
+    }
+});
+
 </script>
 
 </body>