题目内容：
All of our equipment dates back to the 1960s and 1970s; we cannot make products that compete with foreign products, __________we can buy the necessary technology.A. unless
B. while
C. Once
D. if
参考答案：
选择题：All of our equipment dates back to the 1960s and 1
- 题目分类：山西财经大学英语3
- 题目类型：选择题
- 查看权限：VIP
A. unless
B. while
C. Once
D. if