根据句意和所给汉语提示，写出句中所缺单词或短语的正确形式。

1. I used my__________（计算器）,or it will have taken a long time.

2. The__________（微波炉）makes cooking meals easier and quicker.

3. The__________（电灯泡）is the most useful invention.

4. I bought my mother a pair of__________（拖鞋）for her birthday.

5. Don't throw about__________（电池）. They are bad for the environment.