选择疑问句是要用or连接的.Wouldyouliketeaorcoffee?要茶还是咖啡?
但是,否定句不一定把and变成or.or是指任一一种,而and指两者同时.
Didyoubuybreadorbutter?你要买面包呢?还是买黄油?
Didyoubuybreadandbutter?你要买黄油和面包吗?更可能是:你要买黄油面包吗?
Doyouhavebrothersorsisters?你有哥哥或者是姐姐吗?
Doyouhavebrothersandsisters?你哥哥姐姐都(同时)有吗?
仔细体会吧.