What rays are convenient to use when constructing an image of an object in a lens?

It is convenient to use three beams to build an image in a thin lens:
1) The beam passing through the main focus of the lens F after refraction in the lens propagates parallel (along) the main optical axis.
2) A beam parallel to the main optical axis, after refraction in the lens, passes through the main focus F of the lens.
3) The beam passing through the optical center of the lens is not refracted.

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