这两个名词均可表示“行李”之意。
baggage : 不可数名词，在英式英语中指大而重的行李，在美国泛指一切行李。
- How many pieces of baggage do you have?
你有几件行李？ - We had to pay extra for our excess baggage (= our bags and suitcases that weighed more than was allowed).
我们必须得为超重的行李额外付费。
luggage : 多用于英式英语，指旅行者的行李。
- We bought some new luggage for our trip.
我们为旅行买了一些新行李箱。 - Never leave your luggage unattended.
决不要把行李放在没人看管的地方。 - hand luggage (= small bags that you take with you onto the plane)
（可随身带上飞机的）手提行李
