Last year I visited Siberia. I A _____ Lake Baikal. It is a very beautiful deep lake. It is also the B _____ freshwater lake in the world. It is 25 million years old. There are about 100 volcanoes but there are C _____ active ones. 336 rivers flow into Lake Baikal. Only one flows out, which is the Upper Angara. There are more than thirty rocky islands in this lake. One of them is Olkhon. A lot of people D _____ it every year. Lake Baikal is home to thousands of different plants and animals. People like taking photos of E _____. A1) see 2) saw 3) seeing B1) oldest 2) older 3) old C1) some 2) any 3) no D1) visit 2) to visit 3) visiting E 1) they 2) them 3) their