Yes, apple is the singular; the plural form is apples.
analysis itself is a singular form
The noun genius is the singular form, the plural form is geniuses.
The noun form 'cut' is singular; the plural form is 'cuts'.
The singular possessive form of criterion is criterion's
Addendum is the singular form; the plural form is addenda, although there is some acceptance for addendums as the plural.
Apples' would be the plural possessive form of apple. The singular form would be apple's."The apple's taste was bitter to Snow White."
The singular possessive of "apple" is "apple's," as in, "The apple's color was red."
Reaches. Reaches is the third person singular form of reach. You use reaches for he/she/it or singular noun subjects eg She reaches for the apple...... The boy reaches for the apple........... Bob reaches for the apple......... Compare with they (plural) - They reach for the apple.
An apple is a singular noun.
The singular form of the demonstrative pronoun 'these' is this.
The singular form of feet is foot.
You should put "s" after the verb in the present tense when the subject of the sentence is third person singular (he, she, it) and the verb is in base form. For example, "He walks to school every day" or "She eats an apple for breakfast."
The singular form of "hypothysis" is "hypothesis."
The singular form is ombudsman.
it is already in its singular form.
The singular form is hilum.
The singular form is money.