As a waiter you must never neglect or ignore your customers. You must always be wary of your customers' needs and make proper eye contact with them.
 neglect ignoreneglect 就是忽視或忽略的意思
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 risng sea levels.