I have no doubt in saying that anybody could ditch their alarm clock and learn to wake up naturally.

毫无疑问，任何人都可以抛弃闹钟，学会自然醒来。

youdao

For months now I've been waking up ahead of my alarm clock and let me tell you, it feels awesome to wake up on your own and not to the sound of a buzzer.

我们不应该每天都在闹钟的尖叫声中醒来，然后咆哮着将拳头挥向闹钟。 通过几个月的调整，我现在每天都比闹钟早“醒”。

youdao

His alarm clock failed to rouse him, so for the first month he'd use a telephone wake-up service.

他的闹钟没有把他叫醒，所以，第一个月他就采用电话叫醒业务。

youdao

Enough sleep is the amount of sleep that allows you to wake up without an alarm clock.

NPR: Excerpt: 'Delivered from Distraction'

In my case, I stuck with an alarm clock app that offers soothing wake-up calls and nerdy charting features that make for interesting water-cooler talk "My REM was so on last night!"

WSJ: High-Tech Sleep Aids: The Tech to Get Some Z's