the professor wandered from the subject of his speech.

教授偏离了他演讲的主题.
祝你学习进步,更上一层楼!请记得采纳,谢谢!(*^__^*)i could't afford the passage to Australia.那这句呢？我支付不起去澳大利亚的费用。或者：我没有钱去澳大利亚。能不能教我造句？passage（旅费）In fact, by our expenses, I was constantly kept unable to pay my passage.事实上，像我们这样的浪费，已无能力支付我的旅费了。