There are about thirty-one million blacks in the U.S.
美国大约有三千一百万黑人。
《柯林斯英汉双解大词典》
2
I never imagine that one company could have over thirty audiences to communicate with.
我从来没想过一个公司可以与三十多个受众客户进行沟通。
3
In America, people are faced with more and more decisions every day, whether it's picking one of thirty-one ice cream flavors, or deciding whether and when to get married.