根据所给汉语完成单词。
1. Peter didn't _______ (意识到) his mistake at that time.
2. The old man was too tired and he was moving _______ (慢).
3. Don't be _______ (害怕) to ask for help if you need it.
4. I want to _______ (加入) an English club to make more friends who have the same interest.
5. You can _______ (容易) understand if you often listen to it.
1. realize
2. slowly
3. afraid
4. join
5. easily