Syntax: The structure is imperative. 'Now watch me' is a command (imperative mood) followed by the base form of the verb naming the dance move ('whip', 'nae nae'). The parenthetical interjections ('Kill it!', 'Okay!') are exclamations that add encouragement and feedback.
Morphology: 'Whip' and 'Nae Nae' are proper nouns in this context, names of specific dances. They are not conjugated. 'Watch' is in its base form following the imperative structure.

Syntax: This is another imperative command. 'Do' is the imperative verb, followed by the definite article 'the' and the name of the dance 'Stanky Leg.' The repetition of the full phrase creates a rhythmic and emphatic pattern.
Morphology: 'Stanky' is an adjective derived from 'stank' (a colloquial form of 'stunk'), modifying 'Leg' to create a unique compound noun for the dance. 'Do' is in its base form.

Syntax: The structure shifts from 'watch me' to a direct command: 'Break your legs.' 'Tell 'em' is an imperative instructing the listener to relay the command to others. 'Gone and' is an informal, emphatic auxiliary phrase meaning 'go ahead and' or 'proceed to.'
Morphology: 'Break' is the base form of the verb in the imperative mood. 'Your' is a possessive adjective. 'Legs' is the plural noun. 'Gone' is used non-standardly as a particle to add emphasis, not as the past participle of 'go.'

Syntax: Returns to the core imperative structure: 'Now watch me' + [dance move name]. The moves are again treated as proper nouns.
Morphology: 'Superman' is a proper noun used as the name of a dance pose. 'Yuuuuh' is an onomatopoeic interjection, elongated for rhythmic effect.

Syntax: The syntax is minimal: an interjection ('Ooh') followed by the repeated imperative 'watch me.' The lack of a specified action shifts focus to the performer's presence and charisma.
Morphology: 'Ooh' is an interjection expressing excitement. 'Watch' and 'me' are repeated without morphological change, creating a chant-like effect.