△你的句子用 tour to 是完全正确的。

Clare is to make a tour to Australia, her mother has set her luggage in good train. 克莱尔要到澳大利亚去旅行，她母亲已经把她的行李准备停当。

△名词 tour 后面接什么介词，与其用法有关：

1.若表示游览某个地方，其后通常接介词of（不用in）。如：

I suggest a tour of the museum. 我提议去参观博物馆。

The group went on a tour of Italy. 这批人去意大利旅行。

We were given a guided tour of the palace. 我们由导游带领参观游览了那座宫殿。

2.若强调在旅游的地方四处游览，也可用介词around。如：

We went on a guided tour around the castle. 我们在导游的带领下参观了城堡。

We took a tour around New England. 我们到新英格兰各地游览了一圈。

但在许多情况下，用介词of或around区别不大，但总的说来，以用of较为普通。如：

They went on a tour of [round] the city. 他们游历了这个城市。

He made [took] a tour around [of] the world. 他周游了全世界。

3.若表示方向，指去某个地方游览，则可以后接介词to。如：

They arranged a tour to Europe. 他们计划去欧洲旅行。

I’ll make a tour to Europe this summer. 今年夏天我将到欧洲去观光旅行。

She lost her necklace during her sight-seeing tour to Egypt. 她在去埃及观光旅行中丢失了她的项链。