I didn't turn on the light, but groped my way across the room.

我没有开灯，而是摸索着穿过房间。

Please help me turn on the light.

请帮我把灯打开。

He is going to turn on the light.

他准备把灯打开。

Can I turn on the light?

我可以开灯吗？

Please turn on the light. It's dark.

请把灯打开，天黑了。