public function asText(): string
    {
        if ($this->keyword === self::KEYWORD_STILLBORN) {
            // I18N: An individual’s age at an event. e.g. Died 14 Jan 1900 (stillborn)
            return I18N::translate('(stillborn)');
        }

        if ($this->keyword === self::KEYWORD_INFANT) {
            // I18N: An individual’s age at an event. e.g. Died 14 Jan 1900 (in infancy)
            return I18N::translate('(in infancy)');
        }

        if ($this->keyword === self::KEYWORD_CHILD) {
            // I18N: An individual’s age at an event. e.g. Died 14 Jan 1900 (in childhood)
            return I18N::translate('(in childhood)');
        }

        $age = [];

        // Show a zero age as "0 years", not "0 days"
        if ($this->years > 0 || $this->months === 0 && $this->weeks === 0 && $this->days === 0) {
            // I18N: Part of an age string. e.g. 5 years, 4 months and 3 days
            $age[] = I18N::plural('%s year', '%s years', $this->years, I18N::number($this->years));
        }

        if ($this->months > 0) {
            // I18N: Part of an age string. e.g. 5 years, 4 months and 3 days
            $age[] = I18N::plural('%s month', '%s months', $this->months, I18N::number($this->months));
        }

        if ($this->weeks > 0) {
            // I18N: Part of an age string. e.g. 5 years, 4 months and 3 days
            $age[] = I18N::plural('%s week', '%s weeks', $this->weeks, I18N::number($this->weeks));
        }

        if ($this->days > 0) {
            // I18N: Part of an age string. e.g. 5 years, 4 months and 3 days
            $age[] = I18N::plural('%s day', '%s days', $this->days, I18N::number($this->days));
        }

        // If an age is just a number of years, only show the number
        if ($this->years > 0 && $this->months === 0 && $this->weeks === 0 && $this->days === 0) {
            $age = [I18N::number($this->years)];
        }

        $age_string = implode(I18N::$list_separator, $age);

        if ($this->qualifier === self::SYMBOL_LESS_THAN) {
            // I18N: Description of an individual’s age at an event. For example, Died 14 Jan 1900 (aged less than 21 years)
            return I18N::translate('(aged less than %s)', $age_string);
        }

        if ($this->qualifier === self::SYMBOL_MORE_THAN) {
            // I18N: Description of an individual’s age at an event. For example, Died 14 Jan 1900 (aged more than 21 years)
            return I18N::translate('(aged more than %s)', $age_string);
        }

        // I18N: Description of an individual’s age at an event. For example, Died 14 Jan 1900 (aged 43 years)
        return I18N::translate('(aged %s)', $age_string);
    }