下面是王林一周的课程表,仔细阅读后完成所给的问题。 (1) What lesson does Wang Lin have each weekday? (2) How many geography lessons does he have in a week? (3) How many subjects does he study altogether(总共)? 答案:Wang Lin has English each weekday.
He has two geography lessons in a week.
He studies twelve subjects altogether.
普通烟草的叶容易被虫吃掉。科学家发现苏云金杆菌能产生杀虫毒素,于是将苏云金杆菌中产生杀虫毒素的________转入普通烟草的细胞中,而得到抗虫效果良好的抗虫烟草。这种抗虫烟草就是一种________生物,同时也说明生物的性状是由________控制的。人如果长期吸这种抗虫烟草,你认为与吸普通烟草有差别吗?