在PTE考试中，语法是非常重要的一部分，尤其是介词的用法更是需要注意。本文将会从多个角度来分析表原因或理由的介词用法，包括常用的介词、使用时的注意事项以及相关的例句。
一、常用介词
1. because of
because of表示“因为”，后面接名词或代词，通常放在句尾，如：
She couldn't come because of the traffic.
2. due to
due to 也是表示“因为”，常用来作表语和状语，如：
His success is due to hard work and good luck.
3. owing to
owing to 是因为的意思，也常用作表语和状语，如：
The flight was cancelled owing to bad weather.
4. thanks to
thanks to 表示“由于”或“幸亏”，如：
Thanks to your help, I passed the exam.
二、注意事项
1. due to和owing to的区别
虽然due to和owing to都有“因为”的意思，但它们的使用方式是不同的。
due to 是一个形容词短语，只能作表语或定语，如：
His success is due to hard work and good luck.
owing to 是一个介词短语，用作表语或状语，如：
The flight was cancelled owing to bad weather.
2. because of和due to的区别
because of和due to都可表示原因，但because of后接名词或代词，due to后接名词、代词、动名词或从句。
例如：
I was late because of the traffic. (因为交通堵塞，我迟到了。);
His illness was due to overwork. (由于工作过度，他生病了。);
The meeting was cancelled due to the manager's illness. (由于经理病了，会议被取消了。)
三、相关例句
1. She caught the flu because of the cold weather. (她感冒了，是因为天气寒冷。)
2. I missed the train due to the heavy traffic. (由于交通拥挤，我错过了火车。)
3. Owing to the heavy storm, the game was cancelled. (由于暴风雨，比赛被取消了。)
4. Thanks to your advice, I made a great progress. (多亏了你的建议，我取得了巨大进步。)
