题干
--- Roy and Samantha got married last week. Did you go to their wedding?
--- No, I ________ an important meeting in another city.
--- No, I ________ an important meeting in another city.
A：attended
B：have attended
C：had attended
D：was attending
答案(点此获取答案解析）
D
、乙、丙三个品种的苹果，将甲（接穗）嫁接到乙（砧木）上，接穗成活后，再用丙对其授粉，得到的苹果可食部分的性状相似于