四、连词成句。
1. did on you do Children's What Day (?)

2. can save we How energy (?)

3. you Maybe for can a wait sale (.)

4. good Mother They for are Earth (.)

1. What did you do on Children's Day?
2. How can we save energy?
3. Maybe you can wait for a sale.
4. They are good for Mother Earth.

1. 该句是what引导的特殊疑问句，遵循"特殊疑问词+助动词did+主语you+谓语动词do+时间状语on Children's Day"的疑问语序组合即可。
2. 该句是how引导的特殊疑问句，遵循"特殊疑问词+情态动词can+主语we+谓语save+宾语energy"的疑问语序组合即可。
3. 该句是陈述句，副词Maybe置于句首，遵循"主语you+情态动词can+固定短语wait for+宾语a sale"的陈述语序组合即可。
4. 该句是陈述句，用到固定搭配be good for（对……有益），遵循"主语They+be动词are+固定短语+宾语Mother Earth"的陈述语序组合即可。

五、看图片，填写正确的单词或词组，补全句子。
1. We to the new year last night.
2. Many people on the Great Wall yesterday.
3. We use to buy our favourite .
4. Green energy can cars, and .

1. counted down
2. took photos（或took pictures）
3. money; books
4. power; buses; trains

1. 第一题图示为午夜12点人们倒计时迎接新年，句中时间状语last night是一般过去时的标志，“count down to the new year”是固定搭配，意为倒计时迎接新年，动词需要变为过去式。
2. 第二题图示为人们在长城上拍照，时间状语yesterday是一般过去时的标志，“take photos/pictures”意为拍照，take要变为对应的过去式。
3. 第三题图示箭头从钱币指向书籍，句意为我们用钱买最喜欢的书，对应填写符合图意的名词即可。
4. 第四题图示依次展示了新能源汽车、新能源公交车、新能源火车，情态动词can后接动词原形，绿色能源可以为这些交通工具提供动力，依次填写对应内容符合语义和图意。