what is the past particle of kneel?

The four principal parts of any verb are as follows:

present (walk)
simple past (walked)
past participle (walked)
present participle (walking)

I'll give you two more examples:

pray, prayed, prayed, praying
become, became, become, becoming

So ... how will you fill in these blanks?
kneel, ____, ____, kneeling

Check this definition for two correct past participles of kneel.

http://dictionary.reference.com/browse/kneel

The past participle of "kneel" is "knelt" or "kneeled."

To find the past participle of a verb like "kneel," you can follow these steps:

1. Identify the base form of the verb, which in this case is "kneel."
2. Identify the irregularity of the verb. In this case, "kneel" is an irregular verb.
3. Consult a reliable source such as a dictionary or a verb conjugation website to find the correct past participle form.