1) THere are two categories of multi-part verbs:
#1 Synthetic verb form2) To my knowledge, both base salary and basic salary refer to the salary you start at when you join a company. The two, however, can differ. Some employers might use the term base salary to mean that your salary will increase over the term of your employment. For example, "The base salary is ___, and in 6 months it will increase to___". As for basic salary, "The basic salary is ___. There is no increase. Ever." But that is just an example. Some employers might use basic to mean base.
A multi-part verb form expressing one of a variety of possible degrees of pastness, futurity, completeness, habitualness, determination, uncertainty or the like.
Ex: I should have been trying to please them, but I forgot.
#2 Phrasal verbs
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