英语：如果我们星期二下午5点前给不到你SI，最迟要什么时候给你？

If we can't deliver SI to you by 5 PM next Tuesday afternoon, what is the next available time we can deliver?

If we Tuesday before the 17 o'clock to see you, SI, at the latest to be when you?

If we couldn't get your SI by 5pm next week,when will be the last due?

If we couldn't deliver SI to you before 5PM next Tuesday, when's the lasest time we could do so?

虚拟语气，用could。