1个半小时英语可以说作："one and a half hours in English"。

这个表达的来源可能是源于数学中的分数的表达方法。在英语中，分数一般都是用基数词（如one, two, three）加上分数词（如half, third, quarter）来表示的。因此，1个半小时可以说作 one and a half hours。

英文例句：

I will be free for one and a half hours this afternoon.

The movie lasts for one and a half hours.

She has been studying English for one and a half hours every day.