
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
When Xiao Ming calculated the polynomial $M$ minus the polynomial $2x^{2}y-3xy+1$, he mistakenly added the polynomial instead. The result he obtained was $2x^{2}y-xy$.  
$(1)$ Please help Xiao Ming find the polynomial $M$;  
$(2)$ For the polynomial $M$ obtained in $(1)$, when $x=-1$ and $y=2$, find the value of the polynomial $M$.

Present the answer in LaTex format: \boxed{Your answer}
user