fail in的音標是[fe?l ?n]，基本翻譯是失敗，失敗在某方面。速記技巧是可以用拼音聯想記憶，即“失敗因”（fail in）就是“失敗因為”某人或某事而失敗。

fail in的英文詞源：

直接來源：動詞fail的現在分詞形式。

詞源含義：表示“失敗，不及格”。

變化形式：fail的過去式和過去分詞形式。

相關單詞：

1. failure：失敗，不及格；失敗的人或事。源自fail的名詞形式。

2. fail-safe：故障安全，自動安全系統。源自fail的形容詞形式，表示可靠的。

3. fail-fast：快速失敗，快速失敗系統。源自fail的形容詞形式，表示快速的。

4. failed：失敗的，不及格的。fail的形容詞形式，表示失敗或不及格的狀態。

5. fail-safe assumption：安全失效假設，安全失效假設是指系統在出現故障時仍能保持安全性的假設。

6. fail-safe system：安全失效系統，自動安全系統，故障安全系統。

7. fail-to-pass：未能通過考試或測試的人或事物。

8. fail-to-meet：未能達到預期目標或要求的人或事物。

9. failed attempt：失敗的嘗試。

10. fail-in criterion：失敗標準。

英文詞源解析：fail in表示“失敗，不及格”，其詞源可能來自中世紀英語failen，其又可能來自古英語fellan（失敗）。隨著時間的推移，fail in的形式逐漸演變為fail的過去式和過去分詞形式，用于描述失敗或不及格的情況。

舉例說明相關單詞在具體語境中的應用：由于考試難度較大，小明在考試中未能及格，最終fail in了這次考試。為了防止再次fail in，他決定加強復習，提高自己的學習效率。同時，公司為了確保系統安全可靠，采用了fail-safe系統，以確保在出現故障時能夠自動恢復并保持安全性。這些單詞在描述不同場景中的失敗、安全和可靠性等方面具有很強的應用價值。

常用短語：

1. fail in doing sth. 失敗做某事

2. fail to do sth. 未能做某事

3. fail in the exam 考試不及格

4. fail to pass the exam 沒有通過考試

5. fail to meet the deadline 未能按時完成

6. fail to achieve one"s goal 沒有達成目標

7. fail to keep one"s promise 沒有兌現承諾

例句：

1. He failed in the exam twice, and he is very disappointed.

2. We failed to meet the deadline for the project, and it caused a lot of trouble.

3. After years of hard work, he finally failed to achieve his goal of becoming a professional basketball player.

4. She always fails to keep her promise to help others, and this makes people doubt her sincerity.

5. The company failed in the competition because they didn"t have enough resources to compete with their competitors.

6. I failed to complete the task on time because of unexpected difficulties.

7. We all failed to predict the unexpected outcome of the game.

英文小作文：

Failure is a part of life, and it can be a valuable experience that teaches us valuable lessons. Although failure can be painful and disappointing, it can also motivate us to work harder and try again. When we fail, we learn from our mistakes and become stronger and more resilient individuals.

However, failure is not always negative, and it can sometimes be a positive opportunity for growth and development. By learning from our failures, we can become more knowledgeable and skilled, which can lead to success in the future. Therefore, we should not be afraid of failure, but instead embrace it as an opportunity for growth and improvement.