I can't help... 我忍不住……
1. I can't help laughing every time I think of that.
2. I couldn't help noticing your ring, it's beautiful.
3. I can't help remembering how beautiful she looked.
A: So how long have you known Mary?
B: Only four days.
A: Only four days! That's so short, and you seem so crazy about her.
B: I know. I can't help thinking about her. She's always on my mind.