One morning, I didn't want to go to school, and decided to feign illness.

一天早上，我不愿去上学，就决定装病。

《柯林斯英汉双解大词典》

One common scam is for a pair of ne’er-do-wells to feign distress (a broken scooter, an illness) and when you (good samaritan) pull over to help, you are robbed.

一个普通的花招就是一对无用的人让你心生怜悯。 (一辆坏了的脚踏车 一个病痛患者) ，当你(心存善意) 过去帮忙的时候 就被抢了。

youdao

Medical appointments, personal errands and quality time with friends and family were also good enough reasons to feign illness.

CNN: One-third of workers play hooky