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:
| Class | Part 1 | Part 2 | Part 3 | Part 4 | Verb meaning | Usual PIE origin |
| --- | --- | --- | --- | --- | --- | --- |
| 1 | *rīdaną | *raid | *ridun | *ridanaz | to ride | Vowel + y/i. |
| 2a | *freusaną | *fraus | *fruzun | *fruzanaz | to freeze | Vowel + w/u. |
| 2b | *lūkaną | *lauk | *lukun | *lukanaz | to close, to shut | Unknown. |
| 3a | *bindaną | *band | *bundun | *bundanaz | to bind | Vowel + m or n + another consonant. |
| 3b | *werþaną | *warþ | *wurdun | *wurdanaz | to become | Vowel + l or r + another consonant. |
| 4 | *beraną | *bar | *bērun | *buranaz | to bear | Vowel + l, r, m or n + no other consonant. |
Question:
For part 2 *lauk, what is listed for part 4?
Answer:
*lukanaz