Vertical, or opposite, angles are two angles hat have the same vertex and the sides of one the extensions of the sides of the other. (Avery's Plane Geometry, Revised by William C. Stone)
I think the above sentence should be written as follows:
Vertical, or opposite, angles are two angles that have the same vertex and the sides of one are the extensions of the sides of the other.
Do native speakers agree?
Top answer
sitifan t hat Correct. sitifan are Correct.
— Mister Micawber
sitifan t hat Correct.
sitifan are Correct.
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