People didn't go to school by the bus. ____
运用现代生物技术，将苏云金芽孢杆菌的抗虫基因整合到棉花细胞中，为检测实验是否成功，最方便的方法是检测棉花植株是否有( )
Some children prefer to eat junk food ________ it's not good for their health.
