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What will you do if your chocolate falls [on|off|out] the floor? Will you pop it [in|into|out of] your mouth? This is often the case but people forget [about|around|of] the bacteria that are all [around|between|in] us. The solution [to|about|from] the problem is not as simple as you might have thought until now. The point is that instead of fighting [for|to|against] the infection, some microbiologists insist [on|about|up to] contacts with microbes to boost immunity. You may be amazed [that's why|at|thus] the amount of germs left on your hands after washing them without soap. Mind that we are taking bacteria [in|put|on] even through our skin. This means that we can't hide ourselves [off|from|out of] micro-organisms and it is practically impossible to keep the bacteria [off|out of|from] our houses. However, there is no point [of|about|in] doing so because contact with dirt contributes [to|in|into] our immune system. This being said, wash your hands regularly [by|with|of] soap because out of every 9,000 bacteria [over|inside|under] your fingernails, 7,000 are harmless but the remaining 2,000 are extremely virulent.