这个句子有什么语法问题？

In order to improve salary competitiveness of ENG, I advice that G level staff salary couldpromote to RMB3200-3800 per month.

正确的是：In order to improve salary competitiveness of ENG, I advice that G level staff salary (should) be promote to RMB3200-3800 per month.

因为advise是表示建议的动词，它的宾语从句要用should加动词原形，或者省略should,直接加动词原形。advise (sb) (that从句) 主语+ (should) do sth / (should) be done

In order to improve salary competitiveness of ENG, I advise that G level staff salary should be promoted to be RMB3200-3800 per month.
advice是名词，应该用advise
工资被提高，被动句，数字前应加系词be
希望有帮助

could be promoted吧，工资应该是被人提高的