题目内容：
John was busy, ______he could not come.
A but B therefore C and D nor
参考答案：
答案解析：
选择题：John was busy, ______he could not come.A but B therefore C and D nor
- 题目分类： 大学英语B级
- 题目类型：选择题
- 查看权限：VIP
—Mathematics ______ study or science of numbers.A is B are C was D were
—Mathematics ______ study or science of numbers.A is B are C was D were
—Listen! Who ______ in the next room? The voice is so beautiful.A sings B sang C
—Listen! Who ______ in the next room? The voice is so beautiful.A sings B sang C
试比较R-选择和K-选择的主要特征。
试比较R-选择和K-选择的主要特征。
一定地段上，多物种所组成的天然群聚即为（）。
一定地段上，多物种所组成的天然群聚即为（）。
—The audience ______ dressed in a variety of ways, some in suits and dresses,...
—The audience ______ dressed in a variety of ways, some in suits and dresses,...