Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Gothic letter or digraph | Roman equivalent | "Normalised" transliteration | Sound | Normal environment of occurrence (in native words) | Proto-Germanic origin |
| --- | --- | --- | --- | --- | --- |
| �� | a | a | /a/ | Everywhere | /a/ |
| �� | a | ā | /aː/ | Before /h/, /hʷ/ | /ãː/ (before /h/) |
| ���� | ai | aí | /ɛ/ | Before /h/, /hʷ/ , /r/ | /e/, /i/ |
| ���� | ai | ai | /ɛː/ | Before vowels | /eː/ |
| ���� | ai | ái | /ɛː/ | Not before vowels | /ai/ |
| ���� | au | aú | /ɔ/ | Before /h/, /hʷ/ , /r/ | /u/ |
| ���� | au | au | /ɔː/ | Before vowels | /oː/ |
| ���� | au | áu | /ɔː/ | Not before vowels | /au/ |
| �� | e | ē | /eː/ | Not before vowels | /eː/ |
| ���� | ei | ei | /iː/ | Everywhere | /iː/ ; /ĩː/ (before /h/) |
| �� | i | i | /i/ | Everywhere except before /h/, /hʷ/ , /r/ | /e/, /i/ |
| ���� | iu | iu | /iu/ | Not before vowels | /eu/, /iu/ |
| �� | o | ō | /oː/ | Not before vowels | /oː/ |
| �� | u | u | /u/ | Everywhere except before /h/, /hʷ/ , /r/ | /u/ |
| �� | u | ū | /uː/ | Everywhere | /uː/ ; /ũː/ (before /h/) |
Question:
what is the normal environment of occurrence that has a Proto-Germanic origin /ai/
Answer:
Not before vowels