He excused himself on the pretext of a stomach upset.

他借口自己胃不舒服离开了。

辞典例句

He absented himself from the meeting on the pretext of illness.

他假托有病没来开会.

互联网

He came to see me on the pretext of asking my advice.

他以请我指教为借口来看我.

互联网

He stayed away on the pretext of ill health.

他以身体不佳为借口而避开.

互联网