呢兩句tense有咩分別?

你好，以上的解答者都解释得蛮不错的，我也来给你解释以及补充一点点的。
I have been trying... <--- Present Perfect Continuous Tense
I had been trying... <--- Past Perfect Continuous Tense
它们两个最大的分别就是 Present Perfect Continuous Tense 是跟现在有联系的，而 Past Perfect Continuous Tense 是跟过去有联系的，怎么说呢？请你看以下的解释咯。
I have been trying... 可以代表两个意思，一是我已经尝试了和刚刚尝试完了，二是我已经尝试了和现在依然在尝试着。
I had been trying... 也是可以代表两个意思，一是我过去已经尝试了和刚刚尝试完了，二是我过去已经尝试了和讲着过去的那时依然在尝试着。它也是类似 I have been trying... 那样，它只不过比 present perfect continuous 的时间过去了更加久而已，就是在过去了的时间用的。
请看以下的参考资料咯，里面有关于你所问的两个时式/时态 (tense) 的。
希望能帮到你咯。。。: )

The first one is using present continuous tense, it is happening NOW (宜家嘗試緊); the second is past continuous tense, it happened before (之前嘗試過)

I have been trying :
意思系 我一路都嘗試緊

I had been trying :
意思系 我之前一路嘗試


tense既專注點在於"have"既位置
明顯地, 一個系present continous tense
一個系past continous tense