v. 25B6; verb PERSIST, continue, carry on, go on, keep on, keep going, struggle on, hammer away, be persistent, be determined, see/follow something through, keep at it, press on/ahead, not take no for an answer, be tenacious, stand one's ground, stand fast/firm, hold on, go the distance, stay the course, plod on, plough on, stop at nothing, leave no stone unturned; informal soldier on, hang on, plug away, peg away, stick to one's guns, stick it out, hang in there.
give up.