I was asked this question today, but I am unsure how to answer that.
“These others books.”
"This other book."
is correct? I thought other is singular and others is plural.
Other is used both as a noun, and as an adjective.
When using Other as an adjective to describe an object (the "other book"), it will always be used without the s.
However, when using other as a noun identifying the object itself then we have to get the case right -