repeatPrevious(...quantity) {
        const isInteger = /\d+/;
        const values = quantity.filter((argument) => isInteger.test(argument));

        if (values.length === 0 || values.length > 2) {
            return this;
        }

        this.add(`{${values.join(',')}}`);

        return this;
    }
Repeat the previous item exactly n times or between n and m times
@returns {VerbalExpression} recompiled instance of VerbalExpression
@memberof VerbalExpression