三、用所给单词的适当形式填空。
1. Yoyo (remove) the chair before she went away.
2. I (realize) I made a mistake later.
3. There (be) much rain outside last night.
4. He (create) a new kind of toy last year.
5. After trying several ways, they (final) found the solution.

1. had removed 2. realized 3. was 4. created 5. finally

1. 由before引导的时间状语从句用一般过去时，主句动作发生在从句动作之前，需用过去完成时，结构为had+动词过去分词，故填had removed；2. 由语境及later可知动作发生在过去，用一般过去时，故填realized；3. 由last night可知时态为一般过去时，rain是不可数名词，be动词用was，故填was；4. 由last year可知时态为一般过去时，故填created；5. 此处需副词修饰动词found，final的副词形式为finally，故填finally。

四、按要求完成句子，每空一词。
1. Lucy did her homework this afternoon.（改为否定句）
Lucy her homework this afternoon.
2. I cleaned the room last weekend.（对画线部分提问）
you last weekend?
3. The weather was terrible yesterday.（对画线部分提问）
the weather yesterday?
4. My holiday was great.（对画线部分提问）
your holiday?
5. My mother bought me a skirt last Saturday.（改为同义句）
My mother bought a last Saturday.

1. didn't do；2. What did do；3. What was like；4. How was；5. skirt for me

1. 原句是一般过去时，谓语为实义动词do的过去式did，变否定句需借助助动词didn't，后接动词原形do；2. 画线部分是动作，用What提问，一般过去时特殊疑问句结构为“What+did+主语+动词原形+其他”；3. 询问天气的固定句型为“What was the weather like?”；4. 询问事物状况用How，一般过去时be动词提前；5. buy的双宾语结构可转换为“buy sth for sb”。

五、根据汉语意思完成句子，每空一词。
1. 这些东西通常太小以至于看不见。
These things are usually .
2. 我以前认为获取干净的水很容易。
I it was easy to get clean water.
3. 我没有意识到它这么难。
I it was so hard.
4. 工厂把污水变成干净的水。
The plant dirty water clean water.
5. 它让我想起一句话：“粒粒皆辛苦。”
It me the saying, “Every grain from hard work”.

1. too small to see；2. used to think；3. didn't realize；4. turns；into；5. reminds；of；comes

1. 考查固定结构too + 形容词 + to do sth.，表“太……而不能……”，“太小”对应too small，“看不见”对应to see；2. 考查固定搭配used to do sth.，表“过去常常（此处指过去的想法）”，“以前认为”对应used to think；3. 考查一般过去时的否定句，“意识到”对应realize，否定形式为didn't + 动词原形；4. 考查固定搭配turn...into...，表“把……变成……”，主语the plant是第三人称单数，谓语用turns；5. 考查固定搭配remind sb of sth.（使某人想起某事），主语it是第三人称单数，谓语用reminds；“粒粒皆辛苦”中“来自”对应come，主语Every grain是单数，谓语用comes。