If a product contains bleach (peroxide), it will whiten your teeth. But not all treatments are created equal. It's the concentration or percent of hydrogen peroxide a teeth-whitening system contains and the amount of time it's in contact with your teeth that determines its effectiveness.
Definition of fecund - producing or capable of producing an abundance of offspring or new growth; highly fertile Definition of fecund - producing or capable of producing an abundance of offspring or new growth; highly fertile
1. allowance-an amount allowed or granted (as during a given period); travel allowance; my weekly allowance of two eggs; a child's allowance should not be too generous. share, percentage, portion, part-assets belonging to or due to or contributed by an individual person or group; he wanted his share in cash.