26.needs

------>need (vì "the sick" là danh từ  chỉ những người ốm nên động từ theo sau nó giữ nguyên và ta luôn có the+adj sẽ tạo ra danh từ)

27.seriously

------> serious (chỗ đó cần điền là tính từ)

28.to enjoy 

----> enjoying (vì trước đó có "look forward to")

29. since

----> from  (vì "from" sẽ đi với "to")

30.that

----> which (vì "her well - known film" là vật nên dùng đại từ quan hệ "which" để thay thế)

26. The sick needs to be looked after. So money must be spent on hospitals.

needs → need

27. The accident looked seriously at first but nobody was injured. 

seriously → serious

28. All the students are looking forward to spending their free time to enjoy their Tet holiday. 

to enjoy → enjoying

29. My family lived in Hue since 1990 to 1996, but we are now living in Sai Gon.

since → from

30. Her well-known film, that won several awards, was about the life of Lenin. 

that → which