Strange irregular plural forms

Question

I'm struggling with this exercise that I found in a German grammar book: I have to combine some nouns with the correct suffix to form their plural

Nouns:

1. der Schnee
2. das Gepäck
3. der Regen
4. der Rat
5. der Käse
6. der Sport
7. der Schmuck
8. das Alter

Suffixes:

1. stufen
2. waren
3. schläge
4. stücke
5. massen
6. arten
7. sorten
8. fälle

The first one is given as an example: "der Schnee" -> "die Scheemassen".

I haven't got a clue about the other ones (apart from "der Regen" which I think should be "die Regenfälle"). I looked up the nouns in various online dictionaries but I couldn't find these "strange" plural forms (usually the ones given are much more simple, like: -e/-en).

I guess that most of these forms are quite uncommon in both spoken and written German, is that true? Could someone please help me complete the exercise?

Answer 1

You are right about Regen/Regenfälle. Note however, that Regenfälle is not a plural of Regen. The plural of Regen is Regen, but it is rarely used. However, the word Regenfall exists. It denotes, in a sense, one instance of Regen, and it has a perfectly normal plural, which is Regenfälle. So this can be used as a substitute when you need a plural of Regen.

For the others, just check your dictionary which combinations exist.