Please help me 
Please talk about what it is you do not understand in this step? What have you tried?
Welcome to the forum @NaomiSetyaningsih
You placed the span element around the text 8g
As you can see in the preview this made no difference to the alignment.
Try placing the opening span tag after the opening paragraph tag.
Happy coding
For next time, if you have a question about a specific challenge as it relates to your written code for that challenge and need some help, click the Help button located on the challenge. This button only appears if you have tried to submit an answer at least three times.
The Help button will create a new topic with all code you have written and include a link to the challenge also. You will still be able to ask any questions in the post before submitting it to the forum.
Thank you.