"My love," he said, with irritation reined in by propriety, "you may rely upon me for knowing the times and the seasons, adapted to the different stages of a work which is not to be measured by the facile conjectures of ignorant onlookers.
He reined in the mile-an-hour pony (no difficult feat), and saluted the formidable monarch.
Singledom means a lack of responsibilities and responsibility-free people need to be reined in by the wisdom of elders, or they will be reckless with their directionless lives.
"When he was aware of the voice, he looked down and reined in his horse.