"trophy" is the singular from of "trophies"
Most trophies are made in the form of the shape with a mold. Molds would already be made with the tops needed for putting the trophies together.
The singular form of the demonstrative pronoun 'these' is this.
The singular form of "that" is "it."
The singular form is cuff.
it is already in its singular form.
"Stratum" is the singular form of stratum. The plural form is "strata".
The form hypothesis is the singular form. The plural form is hypotheses.
A singular form of dice is a die
The singular form of feet is foot.
The singular form of Oases is, Oasis.
"Wash" is the singular form of "wash."
The singular form of chromosomes is a chromatid.