The word data is already plural. The singular form of the word data is datum.
The plural form of use is uses.
We use is in singular form and are in plural form.
attendees
"Les" means the plural form of "the", while "Des" means the plural form of "some".
The plural form of female donkeys is jennies.
Some people prefer to use the noun trout as an uncountable (both singular and plural) noun. Others prefer to use the plural form trouts. Both are correct.
to represent and compare datas to it.
No, the sentence is not grammatically correct. It should be rephrased to "They were the pranksters."
It is seldom necessary to use the word Harry in a plural form, but if such a situation arises, the plural is Harry's. This should not be confused with harries, which is a verb.
The comings and goings of the president' is a valid use of a plural gerund. It is possible for gerunds to be plural despite how uncommon that is.
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DIRECTRESS