And incumbents often look invulnerable until they suddenly fall .

而且往往出版商在倒下的前一刻还看起来坚不可摧。

The corporation gets 3.6 billion ( $ 5.7 billion ) a year from a licence fee levied on every household that watches television , and is therefore invulnerable to the vagaries of the media market , while the technological change that has caused other media outlets to shrivel has given the bbc new scope for expansion .

公司每年因每户家庭的电视执照费征收可获得36亿英镑（折合57亿美金），因此对于传媒市场的变幻莫测bbc显得坚不可摧，而技术变革所造成的其他传媒渠道的凋零给予了bbc向新领域扩张的机会。

As long as rioters are part of a street mob they feel strong and invulnerable .

这些暴徒只要加入街头暴徒的行列，就会觉得自己无懈可击。

Because they are quiet and constantly moving , they are essentially invulnerable to pre-emptive attack ; there is less pressure to use them or lose them .

因为它们在悄无声息中不断移动，在先制攻击中几乎无懈可击；使用或失去都没有那么大的压力。

These clothes , she says , are meant to convey that he 's a seemingly invulnerable superhero type in the beginning .

她说，一开始让他穿着这些服装，传递的信息是：他是一个刀枪不入的超级英雄。