When something is fitful, it does not go on smoothly. It starts, then it stops, then it starts again. A fitful night is a night when you sleep a little, wake, sleep a little more. Fitful rain comes down hard for a minute and then goes quiet. Fitful effort is work in short bursts, not a steady line. People use it a lot for sleep, wind, rain, and attention — things that come in waves. It is not a kind word: it tells you the thing is broken up. Though actually the fit hiding inside is not the fit of these shoes fit. It is the older fit that means a sudden burst: a fit of coughing, a fit of laughter, a fit of anger.

斷斷續續的；一陣一陣的