使用助动词进行否定：
在助动词do does did后面加not 加实意动词
do not / don't
does not / doesn't
did not / didn't
1、I don't go to school by bus. 一般现在时、主语是非第三人称单数，所以使用don't
我不做公共汽车去学校。
2、She doesn't watch TV everday.单三否定形式。
她每天不看电视。
3、They didn't swim last night. 过去时；didn't否定实意动词的助动词
昨天晚上他们没有游泳。
总结：
过去时时态的助动词没有主语数量上的变化，无论主语是单数还是复数都使用didn't
一般现在时主语时单数第三人称时使用doesn't
主语不是第三人称单数时使用don't
使用助动词进行提问：
助动词放在句首，原句当中的实意动词如果发生时态上的变化要变成原型
1、He often plays golf. 他经常打高尔夫球
Does he often play gollf? 他经常打高尔夫球吗？
Yes，he does./No,he doesn't.
2、They go to school by bus.他们坐公共汽车去学校。
Do they go to school by bus?他们坐公共汽车去学校吗？
Yes,they do./No,they don't.
3、Sam had breakfast yesterday. 山姆昨天吃早饭了。
Did sam have breakfast yesterday?山姆昨天吃早餐了吗？
Yes,he did./No,he didn't.
练习：
1、他每天都学英语吗？（单三用does）
Does he learn English everday?
是的，他每天都学英语。
Yes,he does.
2、Tom 昨天没有吃早饭。（过去式）
Tom didn't have breakfashe yesterday.
