When I answered the door I saw two well-groomed gentlemen who claimed that they are Christians. I started studying the Bible with them and ended up being baptized one year later.
這是一個連環問題: 燃燒石油導致二氧化碳增加，二氧化碳增加導致溫室效應，溫室效應導致冰層融化、海平面上升。 (請填空)
This is a chain of problems. Burning oil leads to increase in carbon dioxide, which leads to the greenhouse effect, which leads to melting of glaciers, which leads to rsing sea levels.