When using the expression 'I have something' you are communicating that you possess something or need to do something that is unspecified or undetermined.  当用'I have something'来表达的时候，你要传达的是你拥有某样东西或需要做一些未指明或未确定的事情。

Here are some examples: 这里有一些例子：

"I have something to complete." 

我有一些事情要完成。

"I have something to share with you." 

我要分享一些事情给你。

"I have something important to tell you." 

我有一些重要的事情要告诉你。

"I have something to encourage you." 

我有一些事情要鼓励你。

"I have something to explain to you." 

我要向你解释一些事情。

"I have something special planned for your birthday." 

为你的生日我有一些特别的安排。

"I have something else to consider." 

我有其他事情要考虑。

"I have something to apologize about." 

我有些事情很抱歉。

"I have something to attend tonight." 

今晚我有其他的事情要参加。

"I have something to ask you." 

我有一些事情要问你。

"I have something fun for us to do." 

我有一些有趣的事情我们可以去做。