A:植物细胞融合必须先制备原生质体
B:试管婴儿技术包括人工授精和胚胎移植两方面
C:经细胞核移植培育出的新个体只具有一个亲本的遗传性状
D:用于培养的植物器官或组织属于外植体
① ____ A. sunny B. spring C. cloudy
② ____ A. nice B. warm C. flower
③ ____ A. hop B. ice C. skate
We can't afford _____ such a high price .
I must leave now. I have to goodbye to you.