Ⅰ. 根据所给首字母及中文释义写出各单词的完整形式
1. He devoted himself to teaching and r_______（退休）at the age of sixty.
2. I can g_______ (保证) that you will be satisfied with the result.
3. The horse t_______ (训练员) knows how to train his horse.
4. New tax rules had given them an a_______ (优势) over their commercial rivals.
5. He works day and night to earn enough money to p_______ (购买) a house.
