There is no time like the present. 现在正是时候
Take time by the forelock. 把握目前的时机
To choose time is to save time. 选择时间就是节省时间
Never put off till tomorrow what may be done today. 今日事，今日毕
Procrastination is the thief of time. 拖延为时间之窃贼
One of these days is none of these days. 改天改天，不知哪天
Tomorrow never comes. 明天无尽头，明日何其多
What may be done at any time will be done at no time. 常将今日推明日，推到后来无踪迹
Time undermines us. 光阴暗中催人才。或莫说年纪小人生容易老
Time and tide wait for no man. 岁月不待人
Time cannot be won again. 时间一去不再来
Time is, time was, and time is past. 现在有时间，过去有时间，时间一去不复返
Time lost can not be recalled. 光阴一去不复返
Time flies like an arrow, and time lost never returns. 光阴似箭，一去不返