The English language is strange (no kidding) you can have this.   We'll begin with a box -- the plural is boxes.  But the plural of ox is oxen, not oxes.  One fowl is a goose, but two are called geese.  Yet the plural of moose, should never be meese. You may find a lone mouse, or a nest full of mice.  Yet the plural of house is houses, not hice. If the plural of man is always called men,  Why shouldn't the plural of pan , always be pen? If I speak of my foot, ans show you my feet,  And I give you a boot, would a pair be called beet?  If one is a tooth, and a whole set are teeth,  Why shouldn't the plural of booth, always be beeth?  One may be "that", and three would be "those",  Yet hat in the plural, can never be hose...  And the plural of cat is cats and not cose. We speak of a brother, and also a brethren,  But though we say mother, we never say methren.  And the masculine pronouns are "he", "his" and "him",  But imagine the feminine -- "she", "shis" and "shim". So the English language, I'm sure you'll agree,  It's the craziest language, you ever did see.