Nowadays the employers use different instruments in order tostimulate their laborers to work better and faster.
... the appropriate word there is "motivate" and not "stimulate" - Employers motivate employees to enhance their productivity.
However, one must admit that the mostcommon way to encourage employees to carry out their duties is money
...
However, we cannot deny that money is one of the best motivators and the one that most commonly used.For example, to put this powerful instrument into use the employers do not need to possess special psychological knowledge on how to make people work
.... this sentence doesn't make much sense... you better rephrase or remove it
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