原式=1356+34+56+712
=16612+912+1012+712
=166+9+10+712
=19212
=16.
用 there be 或 have的适当形式 填空。
1. This desk _________ four legs.
2. __________ some books on the desk.
3. Everyone ___________ a dictionary in my class.
4. ___________ (没有) knives in the room.
5. I ___________ a new sweater.
6. ___________ some flowers and a desk in the room.
7. ___________ nothing in the bag.
8. They ____________ something to eat.
酵母菌的无性繁殖方式很多,最常见应用于发酵工业上的有()
A、芽裂殖
B、芽殖
C、裂殖
D、无性孢子