if not possible

基本解释

Accommodate any guest request, if not possible then offer appropriate alternatives.
满足客人要求，如果不能满足，提供客人另外的选择。
"Any potentially deadly disease is a big problem and … we've got to try to make sure that the spread of this disease is eliminated if possible and minimised if not possible, " he said.
他说：“任何可能致命的疾病都是大问题，我们必须尝试确保把这种疾病的传播，如果可能的话彻底消灭，不可能的话则将其控制在最低水平。”
Try to make a separate space for the patient at home; if not possible, ensure the patient to keep away from others at least one meter.
设法在家中为病人单独辟出一块空间。如果这样做不可行，让病人与其他人至少保持一米远的距离。

If that is not possible, then clean off the equipment and your shoes when leaving.
And so it's not, perhaps, crippling if this is the conclusion we reach, but at the same time it's not the only possible conclusion.
因此，如果这就是我们的结论，也没有太大关系，但同时要知道这不是惟一可能的结论。
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So that means it's not possible, if we've made these stipulations in the first place, to have a case where l equals 1.
这说明我们之前的假设,ｌ等于１不可能的。
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So it's not as if it's not possible to do.
WHITEHOUSE: President Obama Makes a Statement on the Sequester