The final radical of this word is guttural; this affects the adjacent vowels.
Singular
Plural
Absolute State
תִּשְׁעָה
tish'a
nine m.
תֵּשַׁע
tesha
nine f.
Conjugate State
תִּשְׁעַת
tish'at
(the) nine m. of
תֵּשַׁע
tesha
(the) nine f. of
Masculine
Feminine
Person
תְּשַׁעְתֵּנוּ
tsha'atenu
the nine of us
תְּשַׁעְתְּכֶם
tsha'atchem
the nine of you m. pl.
תְּשַׁעְתְּכֶן
tsha'atchen
the nine of you f. pl.
תְּשַׁעְתָּם
tsha'atam
the nine of them m.
תְּשַׁעְתָּן
tsha'atan
the nine of them f.
1st (I) Person
תְּשַׁעְתֵּנוּ
tsha'atenu
the nine of us
2nd (You) Person
Masculine
תְּשַׁעְתְּכֶם
tsha'atchem
the nine of you m. pl.
Feminine
תְּשַׁעְתְּכֶן
tsha'atchen
the nine of you f. pl.
3rd (He/She) Person
Masculine
תְּשַׁעְתָּם
tsha'atam
the nine of them m.
Feminine
תְּשַׁעְתָּן
tsha'atan
the nine of them f.