In Hebrew, there are two patterns, but we go to shelters with an "אזעקה" (az'aka) and not a "הזעקה" (haz'aka). What's the difference between the "הַפְעָלָה" (ha'fala) pattern and the "אַפְעָלָה" (a'fala) pattern?
The "הַפְעָלָה" (ha'fala) pattern is the verb noun of the active binyan. Alongside it, there are names in the "אַפְעָלָה" (a'fala) pattern. Few names in this pattern are found in Rabbinic Hebrew (the language of our sages) – perhaps influenced by the parallel verb noun in Aramaic (from the "אַפְעֵל" (a'fel) construction). In Rabbinic Hebrew, there was no semantic difference between the forms with "א" (alef) and the forms with "ה" (he), and sometimes they reflect different linguistic tendencies. For example, the form "הבדלה" (havdala) is typical of Babylonian Talmudic Hebrew, whereas "אבדלה" (avdala) is typical of Palestinian Talmudic Hebrew.
In some names, a semantic distinction was created between the form with "ה" (he) and the form with "א" (alef): "הזכרה" (hazkara) (the action, such as 'commemorating souls', 'naming participants') versus "אזכרה" (azkara) (a memorial); "הזעקה" (haz'aka) (the action, such as 'calling the police to the scene') versus "אזעקה" (az'aka) (a siren sound activated in times of danger). In other cases, the distinction is a result of term creation. For instance, the term "אסדרה" (asdera) was established as an alternative to 'regulation', alongside the general word "הסדרה" (hasdera), and similarly, there are the terms "אבטחה" (avtacha) versus "הבטחה" (havtacha), "אבחנה" (avchana - diagnosis) versus "הבחנה" (havchana).
Alongside words with a distinguished meaning, there are those where both forms are used interchangeably. For instance: "הזהרה" (hazhara) and "אזהרה" (azhara), "השליה" (hashliya) and "אשליה" (ashliya), "הפליה" (hafliya) and "אפליה" (afliya), "הונאה" (honaa) and "אונאה" (onaa). There are even cases where only the form with "א" (alef) is used, such as "אבטלה" (avtala).
Many linguists, both in the revival period and later, opposed the forms in the "אפעלה" (a'fala) pattern that carried Aramaic undertones, advocating the use of forms in the "הפעלה" (ha'fala) pattern which is the original Hebrew pattern. Therefore, they preferred "המצאה" (hamtzaa) over "אמצאה" (amtzaa), "התראה" (hatraa) rather than "אתראה" (atraa), and so on.