Again, 'I have' shows possession or something acquired. By adding a past participle you are informing someone of a past or completed action done by you. 再一次，'I have'是表明所有权或者得到某物，通过加一个过去分词来告诉别人你在过去或者完成的动作。

Here are some examples: 这里有一些例子： 

"I have done it." 

我已经完成了。

"I have heard that before." 

我在之前就已经听说了。

"I have driven a car." 

我开过车。

"I have forgotten the words." 

我已经忘记那些话了。

"I have read that book." 

我已经读过那本书了。

"I have eaten at that restaurant before." 

我之前在那家饭店吃过饭。

"I have flown in an airplane."

 我坐过飞机。

"I have forgiven you."

 我已经原谅你了。

"I have seen you before."

 我之前见过你。

"I have written a letter." 

我已经写完了一封信了。