3 sentences

1. 许多游客在假期里去杭州观光。

   xǔ​duō yóu​kè zài jià​qī lǐ qù Háng​zhōu guān​guāng.

   Many tourists go sightseeing in Hangzhou during the holidays.

   Source: Dong Chinese Dictionary

2. 威尼斯的小巷里到处都是划船观光的游客。

   Wēi​ní​sī de xiǎo xiàng lǐ dào​chù dōu shì huá​chuán guān​guāng de yóu​kè.

   The narrow alleys of Venice are filled with tourists sightseeing by boat.

   Source: Dong Chinese Dictionary

3. 观光业对当地经济非常重要。

   guān​guāng yè duì dāng​dì jīng​jì fēi​cháng zhòng​yào.

   The tourism industry is very important to the local economy.

   Source: Dong Chinese Dictionary