如果你现在离开课程，你所有的辛勤努力都将付诸东流。

If you leave the course now, all your hard work will go ___down ___the ___drain.

我想，所有这些晚间谈话和10万日元的投资都打了水漂。

All those evening conversations and the investment of 100,000 yen went ___down ___the ___drain, I thought.

由于管理不善，公司的利润都白费了。

The company's profits went ___down ___the ___drain due to poor management.