
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
The following propositions are given:  
① If among four points in space, three are collinear, then these four points must be coplanar;  
② In space, among four points, if any three points are not collinear, then these four points are not coplanar;  
③ Using oblique axonometric drawing, the intuitive image of a trapezoid remains a trapezoid;  
④ Two lines perpendicular to the same line are parallel;  
⑤ A quadrilateral with two pairs of equal opposite sides is a parallelogram. Among these, the correct propositions are.

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