1£®We saw the audience clapping (clap) their hands when the popular singer appeared on the stage.

2£®Where unemployment and crime are high, it can be assumed (assume) that the latter is due to the former.

3£®To my great surprise, he somehow managed to survive (survive) the earthquake.

4£®As an old teacher he has witnessed(witness) the great changes that have taken place in the school in the past thirty years.

5£®It is said that human beings came into existence(exist) about millions of years ago.

6£®It’s true that the world we live in is full of unexplained(explain) mysteries.

7£®We finally managed to make the customers convinced(convince) of the quality of the vehicle.

8£®The film, based(base) upon the true story, attracted people’s interest all over the country.

9£®It occurred to me that she would come to my house for dinner.

10£®It is reported that the police will soon look into the case of the two missing children.

11£®Mr Green is said to have done(do) an experiment to prove the new method of solving the problem when young.

12£®Aliens’ visiting Earth is controversial but what happened in some places is hard to explain, leaving people puzzled(puzzle) about these strange phenomena.

13£®It was getting late when she finally showed up£®

14£®It was getting dark and we made our way to the railway station, arriving there just in time for our train.

15£®Everyone in the village likes Jack because he is good at telling and making up jokes.