NOT UNTILL, ADVERBS OF TIME NOT UNTIL/ TILL+ CLAUSE/ ADV OF TIME, NOT SINCE + AUXILIARY+ S+ V(INF) I WON'T COME HOME TILL 10 O'CLOCK =NOT UNTIL/ TILL O'CLOCK THAT I WILL COME HOME = IT IS NOT UNTIL 10 O'CLOCK THAT I WILL COME IDIDN'T KNOW THAT I HAD LOS...

10. Inversions with : not untill, adverbs of time

Not until/ till+ clause/ adv of time,

Not since + auxiliary+ S+ V(inf)

I won't come home till 10 o'clock

=Not until/ till o'clock that I will come home

= It is not until 10 o'clock that I will come

Ididn't know that I had lost my key till I got home

= Not until/ till I got home did I know that I had lost my key