Explanation

 The captain was filled with growing surprise and disbelief upon realizing that there was no one present in or near the lighthouse. He found it astonishing and unexpected, considering the typical presence of people in such a location.

The writer describes the experience of speeding downhill on a bicycle as a combination of intense excitement and fear. It is a thrilling and exhilarating sensation, yet at the same time, it evokes a sense of terror or apprehension.

Coral reefs are still crucial to people living in the tropics because they serve multiple purposes. They provide a source for manufacturing tools, such as building materials or traditional implements. Additionally, coral reefs hold cultural significance, and their vibrant beauty is used to decorate and embellish houses, adding a touch of natural splendor to the tropical lifestyle.

Coral reefs continue to be vital to people living in the tropics due to their multifaceted importance. These reefs serve as a valuable resource for the local communities, providing materials for tool production and construction. Moreover, coral reefs hold cultural significance and are cherished for their aesthetic appeal, often used to beautify and enhance tropical homes.

Coral reefs remain essential to people in the tropics as they serve practical and decorative purposes. They are utilized for manufacturing tools and construction materials, while also being appreciated for their beauty as adornments in tropical homes.