I have been to Shanghai. I __________ there last month.
A:go
B:went
C:have gone
D:will go
请同学们根据“观察鲫鱼”的实验,回答问题:
①超市提供的有偿塑料袋
②赠送同学的礼物
③向灾区空投的救援物资
④水厂供应的自来水