根据句意、英文解释或汉语意思完成单词的拼写 。 

1. It is too hot and he is very     _   (the state of wanting to drink)．  

2. I said it would happen, and_____ (certainly; in fact) enough it did happen.  

3. I can't_____ (have or keep in the memory) his name.  

4. He used to be____(害怕)of being alone.  

5. I'm_____(恐怕)he has gone to England.

临床上通常将复发性口疮分为________、________和________。