The Temple in the Lake

For questions 13 – 24, read the text below and think of the word which best fits each gap. Use only one word in each gap, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. Note that you will lose points if you ask for hints!
Lake Titicaca, often known as the ‘holy lake’, is situated in South America on the border between Bolivia and Peru. The lives of the people (13) tools and pottery have (14) found on its shores have long remained a mystery. However, scientists taking (15) in an exploration project at the lake have found what they believe to (16) a 1000-year-old temple under the water. Divers from the expedition have discovered a 200-metre-long, 50-metre-wide building surrounded by a terrace for crops, a road and a wall. It is thought that the remains (17) those of a temple built by the Tihuanacu people who lived beside Lake Titicaca before it became a part (18) the much later Incan empire.
‘The scientists have not yet had time to analyse the material sufficiently,’ says project director, Soraya Aubi. ‘But some have (19) forward the idea that the remains date from this period (20) to the fact that there are very similar ones elsewhere.’ The expedition has so (21) this year made more than 200 dives into water 30 metres deep (22) order to record the ancient remains on film. The film, (23) will later be studied in detail, (24) well provide important information about the region.