Clause: CGEL form

A clause is the smallest unit in any language that can express a complete thought or conversational contribution.

A claim about what’s true, or a description of some situation, or a question that seeks an answer, or an instruction that could be followed, or anything of that sort.

The main clause is the one that isn’t enclosed within any larger one. Must have a tense: tense is not optional for a main clause

Declarative

• Almost always: Subject before noun, event the auxiliary.

• Exception: negative modifier (Never had they …)

• Negative, with negative auxiliary verb or auxiliary verb followed by not

• Can also convey question or command

  You will go to the room right now

  That was all you did?

Interrogative

• Closed questions - always have an auxiliary verb before the subject

Will they be careful

• Open questions - wh words.

Imperative

• Directive meaning (orders, requests)

• Plain form verb: Come, Sleep, Help

• Usually no overt subject (understood you)

• If subject appears → addressee: Everybody come down

• Typically not embeddable as complement

Sleep well

Help yourself

Everybody come down

When joined, imperative may not be understood as a directive:

Get it wrong, and they fail you (= If you get it wrong…, conditional-like use)

Actually means: If you get it wrong, they’ll 

Exclamative

A clause type expressing strong emotion, typically introduced by what or how and involving subject–aux inversion absence.

• Only type of clause that can lack NP before the verb

• Can’t be embedded as a complement

• Verb in plain form, uninflected

• If subject appears, it refers to the addressed

What a beautiful day it is!

How quickly she solved the problem!

• “What” or “How”, but ends with exclamation:

How grand it must be, to be the Chosen one

Note: modern English may use pure interrogative form with “!”:

Did we have a blast!

How cool is that! (not how cool that is)

Optative

A minor category used for expressing wishes. These often feel formulaic or archaic.

God save the Queen.

So be it.

Summary

Clause Type	Key Formal Marker	Structural Example
Declarative	Subject before verb	You are ready.
Interrogative	Subject–auxiliary inversion / wh-word	Are you ready? / Who is ready?
Exclamative	What/How + no inversion	How ready you are!
Imperative	Base verb / no overt subject	Be ready.
Optative	Base verb in fixed expressions	Long live the King.