It's important to note that Old English is a very different language from Modern English. While some words have similar forms, their pronunciation and meaning can be quite different.
Here are some examples of how "ær" was used in Old English:
* ær þām (before that)
* ær þonne (before than)
* ær þā (before those)
While "ær" is no longer used in Modern English, its influence can be seen in words like "earlier" and "foremost," which come from the Old English words ǣr and for respectively.