Teachers and pupils both know that teachers cannot use force - and that parents would not tolerate the use of force - so an aggressive manner would soon be seen as an empty threat.

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However, this is probably an empty threat.

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But this is an empty and dangerous threat.

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So it was an empty, costly threat.

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She has also had to accept that the infamous "0300 call" election advertisement was an empty, and unedifying, threat, which diminished her.

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Opposition members of the London Assembly said Mr Johnson's assurances were empty as he had put under threat other schemes including the Greenwich Waterfront Transit - which would connect a whole swathe of commercial and residential areas in east London - and the widening of the North Circular.

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Depending on the jurisdiction, criminal incitement is typically circumscribed by the requirement that the inciting speech be a real threat and not just an empty rant of a wild man.

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While it would be natural for landlords to take back shops they can re-lease, after a brand stops paying rent, the threat of paying tax on empty properties often stops them from doing so.

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His threat, as we suggested two days ago, is empty.

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