There was an occasionally used dual number sandwiched in between singular and plural. It even had its own set of pronouns.

There's also a dual plural in Hebrew, though to the best of of my limited knowledge it has only one common use. My understanding is:

Normal plurals, meaning "two or more" are formed by adding a suffix, the masculine form of which is pronounced -eem (usually transliterated as -im). The obscure suffix meaning "precisely two" is -ayeem, and is used as below.

In English the preposition behind (behind the table} is also used as a noun [get your behind moving). In Hebrew the equivalent preposition, "tachat", is also pressed into service to mean that same noun -- but the nominative form is tachatayeem.