These words refer to moving in the path of someone who has gone before. Follow is the most neutral of these, yielding the fewest overtones. The gap between leader and follower may be slight or great; the motives for following may range from admiring emulation to a desire to catch or kill the leader: soldiers who followed the platoon leader in single file at the interval of a few paces; an expedition to follow the path that Alexander must have taken to the Indian subcontinent centuries before; She followed after him with cries for help; armed detectives following the rout taken by the escaped convict.

Shadow and tail are both extremely informal words that restrict themselves to the act of following out of unfriendly motives; they also suggest a wish to remain unobserved but to stay close to the person being followed . Of the two, shadow suggests a more relentless and short-range action: He assigned a plainclothes man to shadow the woman every second of the day. Tail may suggest a briefer involvement, one at a greater distance: tailing the truck until it had driven beyond the outer suburbs.

Chase and pursue both suggest swiftness or determination: police who commandeered a passing car to chase a escaping thieves. Chase may also suggest the actual driving away of an enemy: She chased the hooligans from her yard. But while chase often suggests unfriendliness, the act may also be done out of sportiveness or high spirits: The boy chased his playmate round the block. It may also suggest an eager, desiring search: a man who chased after women all his life. Pursue , except for its overtones of speed and determination, is almost as devoid of overtones as follow . No situation or motive is necessarily suggested by the word in itself: detectives who purused the murderer through miles of thick scrub; She purused the absent-minded man to give him back the briefcase he had left behind.

Tag suggests close surveillance, either secretively or with the leader’s full knowledge. In the situation of secrecy, the word approaches the meanings suggested by shadow and tail : tagging the man to find out where he lived. In the situation of acknowledge pursuit, the word may suggest the admiring imitation of someone thought of as a model or superior: the child who tagged after his older brother wherever he went.

Trail may suggest a laggard and spiritless following after someone else: hikers who trailed into camp hours after the first ones had arrived. More often it refers to a stealthy pursuing of someone after he has gone on his way, an action that is done by seeking clues as to which way he might have taken: black trackers expert at trailing someone with a day’s start; They used dogs to trail the escaped convicts. When the word pertains to a closer following , it approaches the meaning suggested by tail or pursue .