供暖系统在早上六点自动启动。

The heating ___comes ___on automatically at six in the morning.

她在会议期间感到偏头痛要发作了。

She felt a migraine ___coming ___on during the meeting.

如果你感觉有感染要发作，请立即咨询医生。

If you sense an infection ___coming ___on, consult a doctor promptly.