A unique characteristic of the English modal auxiliary is that unlike main verbs, they don't have "-s" and "-ing" forms. This is why in the particular case of the modal auxiliary "need," it doesn't have the "s" in the sentence "He need not pay to enter the sports arena." The modal "need" is typically used in three grammatical situations: (1) in negative statements, as in "You need not go now"; (2) in questions, as in "Need he go now?" The strange thing about the modal "need" is that it grammatically malfunctions when used in the positive sense. The resulting sentence certainly doesn't sound right: "He need pay to enter the sports arena."

Source: Manila Times August 31, 2022 06:45 UTC