THERE ARE THREE STRUCTURES OF SENTENCES IN ENGLISH: the three structures are also different in reported speech.
1) STATEMENTS
(affirmatives
and negatives):
SB + VB
2) QUESTIONS:
a)
YES/NO Questions: AUX+ SB+ VB....?
b)
Wh- Questions: Wh-pronoun + AUX + SB + VB...?
3)
COMMANDS:
AFFIRMATIVE: INFINITIVE-
NEGATIVE: DON'T +
INFINITIVE