根據(jù)下面句子的意思及所給的漢語提示，寫出空缺處的單詞或詞組的正確形式。
1. If you are ___________ (粗心的), you'll fail the exam.
2. He looks very young, but he's ___________ (實際上) 55.
3. Can you guess how old my grandfather is? We have just celebrated his ___________ (第九十九個) birthday.
4. When I don't know a word, I often ___________ (查它) in the dictionary.
5. When he heard the cry for help, Danny quickly ___________ (穿衣) and ran out to the man.
