
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
Given that the sum of the first $n$ terms of the sequence $\{a_{n}\}$ is $S_{n}$, where $n\in N^{*}$, choose two of the conditions from condition ①, condition ②, and condition ③ as known, and complete the solution:<br/>$(Ⅰ)$ Find the general formula for the sequence $\{a_{n}\}$;<br/>$(Ⅱ)$ Let the geometric sequence $\{b_{n}\}$ satisfy $b_{2}=a_{4}$ and $b_{3}=a_{7}$, find the sum of the first $n$ terms of the sequence $\{a_{n}+b_{n}\}$.<br/>Condition ①: $a_{1}=-3$;<br/>Condition ②: $a_{n+1}-a_{n}=2$;<br/> Condition ③: $S_{2}=-4$.

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