diff --git a/i18n/en.json b/i18n/en.json
index 1ebc3ce..2d41424 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -17,11 +17,30 @@
 	"edtf-month": "month",
 	"edtf-year": "year",
 
+	"edtf-year-unspecified": "some year",
+
 	"edtf-spring": "Spring",
 	"edtf-summer": "Summer",
 	"edtf-autumn": "Autumn",
 	"edtf-winter": "Winter",
 
+	"edtf-date-unspecified": "some",
+	"edtf-date-BC": "BC",
+
+	"edtf-decade": "{{PLURAL:$1|decade|decades}}",
+	"edtf-century": "{{PLURAL:$1|century|centuries}}",
+	"edtf-millennium": "{{PLURAL:$1|millennium|millennia}}",
+	"edtf-decem-millennium": "decem {{PLURAL:$1|millennium|millennia}}",
+	"edtf-hundreds-of-thousands": "{{PLURAL:$1|hundred|hundreds}} of thousands",
+	"edtf-million": "{{PLURAL:$1|million|millions}}",
+	"edtf-tens-of-millions": "{{PLURAL:$1|ten|tens}} of millions",
+	"edtf-hundreds-of-millions": "{{PLURAL:$1|hundred|hundreds}} of millions",
+	"edtf-billion": "{{PLURAL:$1|billion|billions}}",
+	"edtf-tens-of-billions": "{{PLURAL:$1|ten|tens}} of billions",
+	"edtf-hundreds-of-billions": "{{PLURAL:$1|hundred|hundreds}} of billions",
+	"edtf-thousands-of-billions": "{{PLURAL:$1|thousand|thousands}} of billions",
+	"edtf-trillion": "{{PLURAL:$1|trillion|trillions}}",
+
 	"edtf-spring-north": "Spring (Northern Hemisphere)",
 	"edtf-summer-north": "Summer (Northern Hemisphere)",
 	"edtf-autumn-north": "Autumn (Northern Hemisphere)",
diff --git a/src/Model/ExtDate.php b/src/Model/ExtDate.php
index 74ff27d..f5292d8 100644
--- a/src/Model/ExtDate.php
+++ b/src/Model/ExtDate.php
@@ -175,6 +175,27 @@ private function resolveMaxDay( $year, $month ): int {
 		return null === $this->day ? $lastDayOfMonth : $this->day;
 	}
 
+	public function getUnspecifiedYearScale() : int {
+		if ( $this->unspecifiedDigit->unspecified( 'year' ) ) {
+			$ret = $this->unspecifiedDigit->getYear();
+
+			if ( $this->getYear() === 0 ) {
+				return $ret;
+			}
+
+			return $ret + 1;
+		}
+		return 0;
+	}
+
+	public function getSpecifiedYears() : int {
+		return $this->getYear() / ( pow( 10, $this->unspecifiedDigit->getYear() ) );
+	}
+
+	public function isBC(): bool {
+		return $this->unspecifiedDigit->isBC();
+	}
+
 	/**
 	 * This function is applicable for 2-digits placeholders (month, day).
 	 * Means that decimal: 0 < n < 10
diff --git a/src/Model/UnspecifiedDigit.php b/src/Model/UnspecifiedDigit.php
index 50ec03f..1745ce1 100644
--- a/src/Model/UnspecifiedDigit.php
+++ b/src/Model/UnspecifiedDigit.php
@@ -76,6 +76,10 @@ public function getDay(): int {
 		return $this->day;
 	}
 
+	public function isBC(): bool {
+		return ( (int)str_replace( "X", "1", $this->rawYear ) < 0 );
+	}
+
 	public function century(): bool {
 		if ( $this->year == 2 && substr( $this->rawYear, -2 ) == "XX" ) {
 			return true;
@@ -91,4 +95,4 @@ public function decade(): bool {
 
 		return false;
 	}
-}
\ No newline at end of file
+}
diff --git a/src/PackagePrivate/Humanizer/InternationalizedHumanizer.php b/src/PackagePrivate/Humanizer/InternationalizedHumanizer.php
index 66add18..da7aad2 100644
--- a/src/PackagePrivate/Humanizer/InternationalizedHumanizer.php
+++ b/src/PackagePrivate/Humanizer/InternationalizedHumanizer.php
@@ -215,10 +215,7 @@ private function humanizeDateWithoutUncertainty( ExtDate $date ): string {
 		$day = $date->getDay();
 
 		if ( $year !== null ) {
-			$year = $this->humanizeYear(
-				$year,
-				$date->getUnspecifiedDigit()
-			);
+			$year = $this->humanizeYear( $year, $date );
 		}
 
 		if ( $month !== null ) {
@@ -247,7 +244,55 @@ private function humanizeYearMonthDay( ?string $year, ?string $month, ?string $d
 		);
 	}
 
-	private function humanizeYear( int $year, UnspecifiedDigit $unspecifiedDigit ): string {
+	private function scaleToMessageKey( int $scale ): string {
+		switch( $scale ) {
+			case 1 : return 'edtf-year';					// X
+			case 2 : return 'edtf-decade';					// XX
+			case 3 : return 'edtf-century';					// XXX
+			case 4 : return 'edtf-millennium';				// XXXX
+			case 5 : return 'edtf-decem-millennium';		// XXXXX
+			case 6 : return 'edtf-hundreds-of-thousands';	// XXXXXX
+			case 7 : return 'edtf-million';					// XXXXXXX
+			case 8 : return 'edtf-tens-of-millions';		// XXXXXXXX
+			case 9 : return 'edtf-hundreds-of-millions';	// XXXXXXXXX
+			case 10 : return 'edtf-billion';				// XXXXXXXXXX
+			case 11 : return 'edtf-tens-of-billions';		// XXXXXXXXXXX
+			case 12 : return 'edtf-hundreds-of-billions';	// XXXXXXXXXXXX
+			case 13 : return 'edtf-trillion';				// XXXXXXXXXXXXX
+		}
+
+		// FIXME: reuse recursively the scale with trillions
+		// e.g. tens-of-trillions etc., 
+		return 'edtf-tens-of-trillions';
+	}
+
+	private function humanizeYear( int $year, ExtDate $date ): string {		
+		$unspecifiedYearScale = $date->getUnspecifiedYearScale();
+		$unspecifiedDigit = $date->getUnspecifiedDigit();
+		$specifiedYears = $date->getSpecifiedYears();
+
+		if ( $unspecifiedYearScale === 0 ||
+			(  $this->needsYearEndingChar( $unspecifiedDigit ) && $specifiedYears !== 0 ) ) {
+			return $this->humanizeYearSpecified( $year, $unspecifiedDigit );
+		}
+
+		$specifiedYearsStr = (string)abs( $specifiedYears );
+
+		$ret = ( $specifiedYears === 0 && $unspecifiedYearScale != 0 ? $this->message( "edtf-date-unspecified" )
+				: $specifiedYearsStr );
+
+		if ( $unspecifiedYearScale > 0 ) {
+			$ret .= " " . $this->message( $this->scaleToMessageKey( $unspecifiedYearScale ), $specifiedYearsStr );
+		}
+
+		if ( $date->isBC() ) {
+			$ret .= " " . $this->message( "edtf-date-BC" );
+		}
+
+		return $ret;
+	}
+
+	private function humanizeYearSpecified( int $year, UnspecifiedDigit $unspecifiedDigit ): string {
 		$yearStr = (string)abs( $year );
 
 		if ( $year <= -1000 ) {
diff --git a/src/PackagePrivate/Parser/RegexMatchesMapper.php b/src/PackagePrivate/Parser/RegexMatchesMapper.php
index 15e6fae..a768f79 100644
--- a/src/PackagePrivate/Parser/RegexMatchesMapper.php
+++ b/src/PackagePrivate/Parser/RegexMatchesMapper.php
@@ -42,6 +42,8 @@ private function mapDate( array $rawDateMatches ): Date {
 		);
 	}
 
+	// FIXME: ensure that -XXXXXXX4 or -XXXXX4XX throws an error
+	// see https://github.com/ProfessionalWiki/EDTF/pull/88
 	private function prepareNumValue( string $str ): ?int {
 		$value = (int)str_replace( 'X', '0', $str );
 		return $value !== 0 ? $value : null;
@@ -89,4 +91,4 @@ private function regroupMatches( array $matches ): array {
 
 		return $regrouped;
 	}
-}
\ No newline at end of file
+}
diff --git a/tests/Functional/EnglishHumanizationTest.php b/tests/Functional/EnglishHumanizationTest.php
index 7135520..635ef61 100644
--- a/tests/Functional/EnglishHumanizationTest.php
+++ b/tests/Functional/EnglishHumanizationTest.php
@@ -33,6 +33,26 @@ public function humanizationProvider(): Generator {
 
 		yield 'Month only' => [ 'XXXX-12-XX', 'December' ];
 		yield 'Day only' => [ 'XXXX-XX-12', '12th' ];
+		
+		// https://github.com/ProfessionalWiki/EDTF/issues/80
+		yield 'Some year (4 digits)' => [ 'XXXX', 'some millennium' ];
+
+		yield 'Some year (1 digit)' => [ 'X', 'some year' ];
+		yield 'Some year (2 digit)' => [ 'XX', 'some decade' ];
+		yield 'Some year (3 digits)' => [ 'XXX', 'some century' ];
+		yield 'Scales (4 digits minus)' => [ '-5XXXX', '5 decem millennia BC' ];
+		yield 'Scales (5 digits)' => [ '5XXXXX', '5 hundreds of thousands' ];
+		yield 'Scales (6 digits)' => [ '5XXXXXX', '5 millions' ];
+		yield 'Scales (7 digits)' => [ '5XXXXXXX', '5 tens of millions' ];
+		yield 'Scales (8 digits)' => [ '5XXXXXXXX', '5 hundreds of millions' ];
+		yield 'Scales (9 digits)' => [ '5XXXXXXXXX', '5 billions' ];
+		yield 'Scales (10 digits)' => [ '5XXXXXXXXXX', '5 tens of billions' ];
+		yield 'Scales (11 digits)' => [ '5XXXXXXXXXXX', '5 hundreds of billions' ];
+
+		// TODO throw error
+		// yield 'Scales (throw error 1)' => [ 'XXXXXXXXXX4', '' ];
+		// yield 'Scales (throw error 1)' => [ 'XXXXXX4XXXX', '' ];
+
 		yield 'Month and day' => [ 'XXXX-12-11', 'December 11th' ];
 		yield 'Year and day' => [ '2020-XX-11', '11th of unknown month, 2020' ];
 		yield 'Unspecified year decade' => [ '197X', '1970s' ];