Question

If the Chinese gymnast ... (to make/not) a mistake on a vault jump, our Lilia Podkopayeva would not have become the Olympic champion

Answer 1

If the Chinese gymnast hadn't made a mistake on a vault jump, our Lilia Podkopayeva would not have become the Olympic champion.

Answer 2

If the Chinese gymnast had not made a mistake on a vault jump, our Lilia Podkopayeva would not have become the Olympic champion.