我一直不知道这句话是什么意思英语怎么讲

I don't know the meaning of this sentence all along.

I never figure out the meaning of this sentence.

I don't understand this sentence 我不理解这个句子
或者直接用 I don't know the meaning of this sentence. I don't know what the meaning of the sentence is.

I have not known the mean of this sentence all the time

I haven't known the meaning of this sentence till now.