填空题
- A. about one percent of the total population
- B. to be responsible for childhood leukaemia
- C. an urgent and tough task to be accomplished
- D. less than one third of a million
- E. an expensive cost to be paid
- F. to afford the cost of bone marrow transplantation
填空题
It seems that many of the recipients are not rich enough 1.
填空题
Some solvents and building materials are considered 1.
填空题
At present the number of bone marrow donors in mainland China is 1.