一、一般现在时
1．表示经常性或习惯性的动作或存在的状态，常与always, every time, now and then, occasionally, often, seldom, sometimes, usually等连用。
He often gets up at six in the morning.
他经常早上6点起床。
2．表示客观事实或普遍真理。
As we know, light travels faster than sound.
众所周知，光比声音传播得快。
3．常用来表示按时间表、时刻表、日程表等安排将要发生的动作，只限于表示起止的动词如go, come, arrive, leave, start, fly, return等。
The live football match starts at 9 o'clock this evening.
足球实况转播今晚9点钟开始。
