indefinite

会议日期尚未确定。

The meeting is scheduled for an ___indefinite date.

在句子'我想要一杯咖啡'中，'一'是不定冠词。

In the sentence 'I want a cup of coffee', 'a' is an ___indefinite article.

由于施工问题，这座桥将关闭一段不确定的时间。

Due to construction issues, the bridge will be closed for an ___indefinite period.