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Modal verbs and interrogative clauses as directives

410b

Because the bare imperative is considered extremely forceful and in many cases

impolite in English, many directive speech acts (commands, instructions,

requests, etc.) involve interrogative clauses and modal verbs:

Will you look at your handouts, now, please.

Can you shut that door?

These will be dealt with more fully in 412–413.

Interrogative clauses as exclamations

410c

Occasionally, clauses with affirmative or negative interrogative structure can also

be used as exclamations:

[speaker is recounting a long and problematic journey]

Oh God, 

was I exhausted by the time I got home!