diff --git a/examples/probe.rs b/examples/probe.rs
deleted file mode 100644
index 1fdb1a0..0000000
--- a/examples/probe.rs
+++ /dev/null
@@ -1,27 +0,0 @@
-use std::fs;
-use text_processing_rs::tn_normalize_sentence_lang;
-fn main() {
-    let path="/tmp/nemo-parity/tests/nemo_text_processing/en/data_text_normalization/test_cases_address.txt";
-    let (mut p, mut f) = (0, 0);
-    for line in fs::read_to_string(path).unwrap().lines() {
-        let l = line.trim();
-        if l.is_empty() || l.starts_with('#') {
-            continue;
-        }
-        let Some((i, e)) = l.split_once('~') else {
-            continue;
-        };
-        if tn_normalize_sentence_lang(i, "en") == e {
-            p += 1;
-        } else {
-            f += 1;
-            println!(
-                "F [{}]\n  got  [{}]\n  want [{}]",
-                i,
-                tn_normalize_sentence_lang(i, "en"),
-                e
-            );
-        }
-    }
-    eprintln!("address: {}/{}", p, p + f);
-}
diff --git a/src/tn/en/electronic.rs b/src/tn/en/electronic.rs
index 8fcd5e4..563bca7 100644
--- a/src/tn/en/electronic.rs
+++ b/src/tn/en/electronic.rs
@@ -37,6 +37,10 @@ lazy_static! {
     /// Product acronyms upper-cased in email/URL context.
     static ref BRAND: HashSet<&'static str> =
         ["nvidia", "cuda", "dgx", "rtx", "basepod"].into_iter().collect();
+
+    /// File-extension acronyms upper-cased when they are the final ".ext".
+    static ref EXT_UPPER: HashSet<&'static str> =
+        ["html", "htm", "xml", "css", "json", "php", "asp", "sql"].into_iter().collect();
 }
 
 /// Parse an email or URL to spoken form.
@@ -221,6 +225,18 @@ fn render_remainder(s: &str, context: bool) -> String {
         }
     }
     flush(&mut buf, &mut out);
+
+    // Upper-case a known acronym file extension in the final ".ext" label
+    // ("intro.html" → "… dot HTML"), leaving an identically-named directory
+    // ("…/html/…") lower case.
+    let n = out.len();
+    if n >= 2 && out[n - 2] == "dot" {
+        let lower = out[n - 1].to_ascii_lowercase();
+        if EXT_UPPER.contains(lower.as_str()) {
+            out[n - 1] = lower.to_ascii_uppercase();
+        }
+    }
+
     out.join(" ")
 }
 
diff --git a/src/tn/en/measure.rs b/src/tn/en/measure.rs
index a9a57bd..fbc7d51 100644
--- a/src/tn/en/measure.rs
+++ b/src/tn/en/measure.rs
@@ -145,6 +145,12 @@ pub fn parse(input: &str) -> Option<String> {
             continue;
         }
 
+        // A spaced 4-digit decade ("1980 s") is not "1980 seconds" — leave it
+        // to the date tagger, which reads it as "nineteen eighties".
+        if unit_str == "s" && is_spaced_decade(num_part) {
+            continue;
+        }
+
         // Scale word between the number and unit ("100 million kg").
         if let Some(scaled) = parse_scaled(num_part) {
             return Some(format!("{} {}", scaled, unit_info.plural));
@@ -213,6 +219,13 @@ pub fn parse(input: &str) -> Option<String> {
     parse_per(trimmed)
 }
 
+/// A 4-digit multiple of ten ("1980") — a decade written before a spaced "s".
+fn is_spaced_decade(num: &str) -> bool {
+    num.len() == 4
+        && num.chars().all(|c| c.is_ascii_digit())
+        && num.parse::<u32>().map(|n| n % 10 == 0).unwrap_or(false)
+}
+
 /// Read a "value/unit" form where the right side is a bare unit.
 fn parse_per(input: &str) -> Option<String> {
     let (left, right) = input.split_once('/')?;
diff --git a/src/tn/en/serial.rs b/src/tn/en/serial.rs
index f704c44..b2b4c9c 100644
--- a/src/tn/en/serial.rs
+++ b/src/tn/en/serial.rs
@@ -56,6 +56,21 @@ pub fn parse(input: &str) -> Option<String> {
         return None;
     }
 
+    // Rate notation: "<digits>/<single letter>" → "<cardinal> per <LETTER>".
+    if let Some((num, unit)) = token.split_once('/') {
+        if !num.is_empty()
+            && num.chars().all(|c| c.is_ascii_digit())
+            && unit.len() == 1
+            && unit.chars().all(|c| c.is_ascii_alphabetic())
+        {
+            return Some(format!(
+                "{} per {}",
+                number_to_words(num.parse().ok()?),
+                unit.to_ascii_uppercase()
+            ));
+        }
+    }
+
     let mut out = String::new();
     let mut chars = token.chars().peekable();
     while let Some(&c) = chars.peek() {
diff --git a/tests/parity_baseline.tsv b/tests/parity_baseline.tsv
index c49e7fd..e2742d1 100644
--- a/tests/parity_baseline.tsv
+++ b/tests/parity_baseline.tsv
@@ -49,9 +49,9 @@ en	itn	word	55	55
 en	itn	word_cased	49	49
 en	tn	address	8	11
 en	tn	cardinal	18	18
-en	tn	date	52	54
+en	tn	date	53	54
 en	tn	decimal	12	12
-en	tn	electronic	40	45
+en	tn	electronic	41	45
 en	tn	fraction	16	16
 en	tn	math	4	4
 en	tn	measure	11	21
@@ -62,7 +62,7 @@ en	tn	punctuation	39	63
 en	tn	punctuation_match_input	4	13
 en	tn	range	19	20
 en	tn	roman	4	4
-en	tn	serial	27	32
+en	tn	serial	28	32
 en	tn	special_text	9	10
 en	tn	telephone	20	20
 en	tn	time	21	21