`1.` She went to her friend's birthday party last sunday.

- DHNB: Lan didn't go to school, but she went to her friend's birthday party.

`2.` She bought for her friend some gifts and flowers.

- DHNB: She got up early in the morning, went to the shop, and bought some gifts and flowers.

`3.` She ate a lot of cakes and drank soft drink, she danced, sang many songs and told a lot of interesting stories. 

- DHNB: She ate a lot of cakes and drank soft drink. She danced beautifully, sang many songs, and told a lot of interesting stories.

`4.` Yes,they did.

- DHNB: They were very happy and enjoyed thenselves a lot.

`5.` They went home late in the evening after the party finished.

- DHNB: Finally, the party came to an end. They said goodbye to each other and went home late in the evening.

Xin hay nhất ạ

1 last sunday she went to her friend's birthday party (chủ nhật vừa rồi cô ấy đã đi dự tiệc sinh nhật của bạn mình)

2 she bought some gift and flowers for her friend (cô ấy đã mua một số món quà và hoa cho bạn của cô ấy)

3 she ate a lot of cakes and drank soft drink, she danced, sang many songs and told a lot of interesting stories (cô ấy đã ăn rất nhiều bánh và uống nước ngọt, cô ấy đã nhảy múa, hát nhiều bài hát và kể rất nhiều câu chuyện thú vị)

4 yes, they did (vâng, họ đã làm)

5 they went home late in the evening (họ đã về nhà vào buổi tối muộn)