fell back的音標是[fe?l b?k]，意思是“落后；退后；跌倒；衰退；退卻”。

速記技巧：可以嘗試使用諧音記憶，比如“費了巴克它”。

希望以上信息對您有幫助。建議您可以查閱相關資料或請教別人來更好地記憶單詞。

fell back的英文詞源是：

fell：來自中古英語 fele，意為落下，掉下。

back：表示向后。

fell back的意思是“落后，退后”。這個詞組在英語中比較常見，其變化形式如下：

fell back on：依靠，依賴。當人們面臨困難時，他們可能會“退后”并依靠其他資源或方法來解決問題。

fell behind：落后。這個短語描述了一個人或團體在某個方面沒有跟上其他人或團體的進度。

相關單詞有：

1. retreat：撤退，退卻。這個詞源于拉丁語，意為“向后移動”。

2. lag：落后，滯后。這個詞源于古英語，意為“掉落，滯后”。

3. backward：向后的，落后的。這個詞由backward和ward兩個部分組成，ward意為“向內，向后面”。

4. retrace：回顧，追溯。這個詞的意思是“向后移動，追溯”。

5. regress：退步，倒退。這個詞的意思是“向后移動”，引申為“退步”。

以上這些單詞都與fell back有密切的聯系，描述了向后移動的不同含義和用法。fell back在不同的語境中可以表示不同的含義，但總體上都是指后退、落后或依賴其他資源或方法來解決問題。

短語：

1. fall back on

2. fall back into

3. fall back on sb

4. fall back on sth

5. fall back on a plan

6. fall back on one"s wits

7. fall back on one"s luck

例句：

1. If you fail to complete the task, you should fall back on other means to achieve your goal.

2. She fell back on her family for financial support after her divorce.

3. He fell back on his wits to make a living after he lost his job.

英文小作文：

標題：Life After Failure

Life is full of ups and downs, and failure is inevitable. Sometimes we fall back after hitting a brick wall, but it doesn"t mean we give up. Instead, we should learn from our mistakes and try again. We can turn our weaknesses into strengths by seeking help and learning new skills. We can also rely on our family and friends for support and encouragement, which can help us stay motivated and keep going when things get tough. In the end, failure is just a stepping stone to success, and we should never give up hope or despair. Instead, we should keep moving forward and seize every opportunity to improve ourselves and our lives.