He failed the math exam because he didn't study hard enough.（他数学考试没及格，因为他学习不够努力。）

The experiment failed due to a problem with the equipment.（由于设备出现问题，实验失败了。）

She failed to catch the early bus and was late for work.（她没能赶上早班车，上班迟到了。）

Their business venture failed after only a few months.（他们的商业冒险仅仅几个月后就失败了。）

The team failed to score a goal in the entire game.（这支球队在整场比赛中都没能进一个球。）

I failed to understand the complex instructions.（我没能理解那些复杂的说明。）

His attempt to climb the mountain failed because of bad weather.（由于天气恶劣，他攀登那座山的尝试失败了。）

The plan failed because of a lack of proper planning.（由于缺乏妥善规划，这个计划失败了。）

They failed to reach an agreement during the negotiation.（他们在谈判中未能达成协议。）

The company failed to meet its sales targets this quarter.（这家公司本季度未能达到销售目标。）

She failed to remember his birthday, which made him sad.（她忘了他的生日，这让他很伤心。）

The project failed mainly because of insufficient funds.（这个项目失败主要是因为资金不足。）

He failed to pass the driving test for the second time.（他第二次驾照考试没通过。）

Our efforts to save the endangered species failed unfortunately.（很不幸，我们拯救濒危物种的努力失败了。）

The new policy failed to achieve the expected results.（新政策未能取得预期效果。）

They failed to solve the difficult problem despite their best efforts.（尽管他们尽了最大努力，还是没能解决那个难题。）

The play failed to attract a large audience.（这部戏剧没能吸引大量观众。）

I failed to lock the door when I left home this morning.（今天早上我出门时忘了锁门。）

Her dream of becoming a famous singer failed to come true.（她成为著名歌手的梦想没能实现。）

The rescue operation failed because of the dangerous conditions.（由于危险的环境，救援行动失败了。）