请仔细帮我看看这句话,有没有语法问题、介词习惯用法错误、结构不良等等,

全句就一个地方用的不恰当,就是greatly(副词)的位置,副词可以修饰形容词,这里greatly不能后置修饰beneficial,必须前置.
当然有其他的情况,如副词后置修饰前面的形容词：beautiful enough.
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问题补充：bearycx:
前置是否变成
I do believe it will be greatly beneficial to my further study.
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是的.在事情确定前,或是表达一种主观意愿的想法,建议把“will”改成“would”,当然用will也可,表示强烈的愿望或极为肯定的语气

I believe that it will greatly benefit my study in the future.
I believe that it will have great benefits for my further studies.