根据句意及汉语提示完成单词。
1. After a long illness, he could _______ (几乎不)walk by himself.
2. The more _______ (锻炼) you take, the stronger you will be.
3. There is a beautiful park _______ (在……之间)my home and the school.
4. To our _______ (惊讶), the paper factory is still pouring polluted water into the Huai River.
5. Alice has a _______ (习惯)of listening to music while doing homework.
6. The volunteers have planted more than two _______ (千)trees along the river.
7. Our school invited a _______ (科学家) to give us a speech on space.