The six forms change with the addressee's number and gender.
For masculine addressees: اُنْصُرْ — اُنْصُرَا — اُنْصُرُوا (one man, two men, a group of men).
For feminine addressees: اُنْصُرِي — اُنْصُرَا — اُنْصُرْنَ (one woman, two women, a group of women).
The dual form اُنْصُرَا is the same for masculine and feminine addressees.
اللَّهُمَّ انْصُرْ مَنْ نَصَرَ دِينَ مُحَمَّدٍ — O Allah, help whoever helps the religion of Muhammad.