It is difficult to guard against a covert attack or hidden scheme; one cannot easily prevent unexpected malicious actions.
在复杂的商业竞争中，我们不仅要做好自己的产品，更要警惕那些暗箭难防的手段
In complex business competition, we must not only excel in our own products but also be wary of insidious tactics that are hard to guard against.
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