Is this tourist attraction　　　you paid a visit to several days ago?

The moment the 29th Olympic Games _____ open, the whole world cheered.[ ]

33Not until he called the secretary three times ______ that the manager went to an important meeting

I think it’s better to give it a second thought so many of us consider it a risk．

I don’t like the way _______Tom speaks to his motherWhich one is wrong?