Some words in the English language appear to be similar in meaning, but on closer examination we can tell that they have either a positive or negative effect on the reader.
John left Sarah at the side of the road.
John abandoned Sarah at the side of the road.
In the first sentence the verb left is neutral: the reader doesn't know whether John has done a good or a bad thing. However, the verb abandoned has a negative connotation, or effect, and the reader knows that John has done a bad thing by leaving Sarah at the side of the road.
Writers choose their words very carefully to create the effect they are seeking, and often readers are not aware that their feelings are being manipulated by the writer's choice of words.
In this worksheet you can think about the connotations of different words. You may find a dictionary helpful.