Dear Yong Peng,

I appreciate your nicely put presentation here. I'm pointing out a
couple of mistakes.

<< Below is the latest compilation on the word bhaavayato. Please
correct me if there is any mistake.

bhaavayato [referring to A Practical Grammar of the Pali Language by
Charles Duroiselle]
ROOT: bhuu, to be.
Chapter 10
(§492) causative: bhaave, bhaavaya.
(§496) causative base/stem: bhaaveti.>>

I'd say that the causative base/stem is as §492: bhaave, bhaavaya
which are derived from bhuu + .ne or .naya (the .n is an indicatory
letter indicating that the root vowel, where applicable, is
lengthened). Bhaaveti is a causative verb, 3rd pers. sing. active
present tense.

<<(§441) present participle: bhaaventa, bhaavaya.m, bhaavayanta,
bhaavayamaana.
--> Choose 'bhaavaya.m'.>>

In terms of present participle stems, I'd leave out 'bhaavaya.m' as it
is an inflected word in the nom. sing. and choose instead
'bhaavayanta' from bhaavaya + nta.

<<Warder's Lesson 21 (Page 169)
Declension of present participles in -ant: bhaavaya.m ==> bhaavayato
(dat./sing.)
[ The following is based on messages from Jim Anderson and Nina van
Gorkom. ]
Bhaavayato is a present participle derived from a causative stem --
bhaaveti.>>

Use causative stem 'bhaavaya' instead of 'bhaaveti'. The causative
present participle stem is 'bhaavayanta'.

<< There are several variants of the present participle:
bhaaventa, bhaavaya.m, bhaavayanta, bhaavayamaana. In this sutta,
bhaavaya.m is used. The final word bhaavayato can be in either dative
or genitive case. In the context of this sentence, the dative case is
implied.>>

Leave out 'bhaavaya.m'.

Best wishes,
Jim