2: We can use inversion instead of 'if' in conditionals with 'had' 'were' and 'should'. This is quite formal
Normal conditional:
If I had been there, this problem wouldn't have happened.
Conditional with inversion:
Had I been there, this problem wouldn't have happened.
3: We can use inversion if we put an adverbial expression of place at the beginning on the sentence. This is also quite formal or literary
On the table was all the money we had lost.
(Normal sentence: All the money we had lost was on the table.)
Round the corner came the knights.
(Normal sentence: The knights came round the corner.)
4: We can use inversion after 'so + adjective...that':
So beautiful was the girl that nobody could talk of anything else.
(Normal sentence: the girl was so beautiful that nobody could talk of anything else.)
So delicious was the food that we ate every last bite.
(Normal sentence: the food was so delicious that we ate every last bite.)
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