Allergy or Allergic? Choosing Suitable Word Type

My students often choose wrong words when writing their essay. They use adjectives when they should be using nouns, or vice versa. Health vs healthy; important vs importance; the list goes on and on. 

Consider these examples (taken from their essays):

1. Justin Bieber's successful has shown that with hobby, he became famous. 

2. They just think about the comfortable of their children and forget the most important thing which is love between parents and children.

In the first example, the student use successful (berjaya) instead of success (kejayaan) while in the second example (taken from another student), the student choose the word comfortable (selesa) in the place of comfort (keselesaan). In both cases, they do not know they should be using a NOUN instead of an ADJECTIVE. 

Now, before I go further, let's watch a clip from the movie Big Hero 6. 

The words I want to focus on are ALLERGIC and ALLERGY. Let us see where Baymax uses these words:

Here Baymax says: You ARE not allergic to Bacitracin. The verb ARE is used here to show Hiro's attribute, which is NOT ALLERGIC (an adjective) to Bacitracin. We use ADJECTIVES to describe people's attributes, therefore we put an adjective here instead of a noun. In Bahasa, it roughly means: 'alah kepada'.

Here, however, Baymax says: You do HAVE a mild allergy to peanuts. The verb HAVE is used here to show that Hiro has something (a noun). That THING must be a noun, whether it is a concrete noun or an abstract noun. Allergy is an abstract noun showing condition where a person is allergic to something. In Bahasa, it means 'alahan'. 

Well, students. Please choose carefully. Do you really mean 'alah kepada' or 'alahan'? That is the million-dollar question.