1. I have come to realize that the most important thing in life is to make other people happy.2. The water level of the ocean rose gradually.3. At first I don't like the dog. After spending time with him, I begin to like the dog little by little.
 come to gradually little by little< >
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 problem. Burning oil leads to increase in carbon dioxide, which leads to the greenhouse effect, which leads to melting of glaciers, which leads to rising sea levels.