Пример:
There was a conference in London last .(not,take part)
But you didn' take part in it,did you?
Yes ,I did.(No,I didn't).

1. I had a party at my place on Saturday.(not,invite Mike)
2.I wrote a letter to him some days ago.(not,send)
3.I was at the Baltic Sea this summer.(not,swim much)
4.I took my English exam on Friday.(not,pass)
5.I saw Robert yesterday, ( not, speak to him)
6.There was a picnic last wekend.( not, join it)