[kǒng pà]

I'm afraid it won't do.
恐怕不成。

I'm afraid I can't come.
我恐怕不能來。

“Are we late?” “I'm afraid so.”
“我們遲到了嗎?” “恐怕是遲到了。”

I am afraid not.
恐怕不是這樣吧!

Perhaps they are in need of our help.
他們恐怕需要我們的幫助。

It is probable that he has forgotten.
恐怕他是忘了。