如果继续拖欠还款，他可能会面临房贷违约。

He risks ___defaulting on his mortgage if he keeps missing payments.

他因未参加期末考试而挂科了。

He failed the course due to ___defaulting on the final exam.

如果你不做任何选择，系统会自动使用默认设置。

The system will apply the ___default configuration if you don't make a selection.