优质解答
1.一般情况下,and 连接肯定的并列成分.
or 连接否定的并列成分.
如果要表示两个否定的意思,and 后要加no
例如：
There is no air or water on the moon.
= There is no air and no water on the moon.
2.
I want an apple and an orange.
Which do you want,an apple or an orange?
改为选择问句用or 表示两个中选一个.
Tom and his friends are playing football.
What are Tom and his friends doing?
改为其它疑问句and不变,可以用.
1.一般情况下,and 连接肯定的并列成分.
or 连接否定的并列成分.
如果要表示两个否定的意思,and 后要加no
例如：
There is no air or water on the moon.
= There is no air and no water on the moon.
2.
I want an apple and an orange.
Which do you want,an apple or an orange?
改为选择问句用or 表示两个中选一个.
Tom and his friends are playing football.
What are Tom and his friends doing?
改为其它疑问句and不变,可以用.