1. Tourism was then still in its infant stage.
    旅游业当时还处在初创阶段。

2. Tourism is a service industry.
    旅游业是一种服务业。

3. Advertising has played a large part in the growth of tourism, when hotels and travel agencies began to advertise the attractions of different tourist areas, the airlines and other transportation companies advertised the low fares to reach them.
    广告业对旅游业的发展起了很大作用。当旅馆和旅行社做旅游胜地的广告时，航空公司和其它运输公司就做开了到达这些地方的便宜票的广告。

4. Modern means of transportation, communication, advertising and credit have all played a part in the growth of a giant new industry, tourism.
    现代交通、通信、广告以及信用手段对新兴的庞大的行业——旅游业的发展起到了作用。