I can't go any faster.
我不能走得更快了。
I can't remember the combination.
我不記得密碼鎖的數碼組合了。
I can't stand his brother.
他弟弟讓我受不了。
My mum says I can't go.
我媽説我不能去。
I can't make it, unfortunately.
很遺憾,我來不及。
I can't possibly tell you that!
我絕不會把那件事告訴你的!