1.
a. Look, I (have) two tickets for the circus.
b. Look, I (hold) two tickets for the circus.

2.
a. We (be) there for more than half an hour by the time the show began.
b. We (wait) there for more than half an hour by the time the show began.

3.
a. Sam (sit) in the seat next to me when the clown threw a bucket of water at me.
b. Sam (be) in the seat next to me when the clown threw a bucket of water at me.

4.
a. One clown was juggling while he (balance) a glass of wine on his head.
b. One clown was juggling while he (have) a glass of wine on his head.

5.
a. I (love) the circus ever since I was a child.
b. I (go) to the circus ever since I was a child.

6.
a. Right now, I (see) two elephants doing tricks in the ring.
b. Right now, I (look) at two elephants doing tricks in the ring.