1.impossible to defend or excuse
2.impossible to tolerate or endure
3.impossible to support physically in order to prevent collapse
1.Thriving in the dark leads to an unsupportable future, sowing the seeds of destruction within its own foundations.
在黑暗中的兴旺导致一种难以承受的未来，在它自身的根基内播种毁灭的种子。
2.London is a busy place; it would simply be unsupportable if the British behaved as you do.
伦敦是个繁忙的地方，如果英国人都像你一样，还不乱了套。
3.A court is not bound to credit bald assertions, unsupportable conclusions, and opprobrious epithets woven into the fabric of the complaint.
法庭不必采信由枯燥的断言，没有根据的结论和无理的绰号所编织的诉求。
4.Second , Social Security costs could prove unsupportable for the federal budget as a whole .
第二，社会保险成本被证明对整体的联邦预算而言是不可承受之重。
5.But forced austerity has triggered big drops in national outputs, so the debt burdens become even more unsupportable.
不过这种强制的节俭已经造成国家产出的急剧下降，故债务的负担将越来越重。