I was also taught the same thing in school around 40 years ago A perfect vacuum would be one with no particles in it at all, which is impossible to achieve in practice +1 it seems that vacuum is the odd word out when placed in a lineup with (for example) continuum, individuum, menstruum, and residuum
MRCARTOOL T80 Automotive Smoke Machine Leak Detector with Built-in Air Pump EVAP Vacuum Smoke
What's the difference between at hand, on hand and in hand
At hand seems to me as if you have something in reach
On hand is if you have something in stock And in hand can be used as if you have. Overall, emptiness is only about twice as common as nothingness, but emptiness in her heart is about 1000 times more common than nothingness in her heart But both words, along with void, vacuum etc
[can] mean much the same thing. Considering their primary meanings, vacuum is used more often in a scientific context, in which case it means space completely or partially absent of any matter/air Is it necessary to put an article before the word "vacuum" If a 'vacuum cleaner cleaner' is a machine for cleaning vacuum cleaners, then the person who cleans the vacuum cleaner cleaner would be a 'vacuum cleaner cleaner cleaner'.
In other words, don't talk about how the vacuum cleaner was made in germany and incorporates the latest technology
Tell the client he'll be able to vacuum the house in half the time and he'll never have to buy a replacement bag.