It is impossible to defend against an all-out attack.

防御全面进攻是不可能的。

《牛津词典》

Because the Shaozi is quite short and small, it is agile and has strong force of punching, thus it usually makes the opponent impossible to defend effectively.

由于梢子头比较短小，灵活性很大，所以击打力也非常强大，往往令对手防不胜防。

youdao

Then, in a serene but firm manner, Luke begins to defend his rights, employing arguments so contradictory that it is impossible to understand what point he is actually trying to make.

然后，Luke会用一种平静但是坚定的态度开始维护自己的权利，用这一种自相矛盾的争辩方式，根本就不可能理解他到底想阐述什么观点。

youdao

(...) Yigal Palmor. "This diktat is phrased in very extreme terms that try to impose rules that will make it impossible for any country to defend themselves against terror,"

VOA: standard.2009.10.16

Most supporters of the law, however, use more nuanced arguments that depend on assumptions that are increasingly impossible to defend.

WSJ: Daniel Kessler: ObamaCare's Broken Promises

The giant retailer argues that it is impossible to defend the case, since promotion and dismissal decisions are made on an individual basis.

ECONOMIST: A woman's place is in the courtroom | The

Following either of those strategies will force your opponent to block, setting you up to play a square that will give you two rows with which to get tic-tac-toe, impossible to defend.

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