When you’re selecting multiple entities, it’s easy to grab an entity you didn’t want or to miss an entity that you need. To add or remove entities from a selection set, make sure the Select tool is activated; then adjust your selection by using the keyboard modifiers
To Add to the selection set (either a single entity or a selected group of entities)
Hold Ctrl (Microsoft Windows) or Option (macOS)
While selecting an entity or group of entities
To change an entity’s selection status. (Select an unselected entity or clear a selected entity)
Hold Shift
While clicking an entity
To subtract from the selection set
Hold Shift+Ctrl (Microsoft Windows) or Shift+Option (macOS)
While selecting an entity or group of entities
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