• hw,
• fi,
• hai,
• hihg,
• tehi,
• hei,
• hx,
• hiy,
• hic,
• hig,
• wshi,
• hpi,
• shi,
• hk,
• hy,
• hir,
• hik,
• whi,
• ohia,
• chx

• mi,
• mi.,
• ha,
• HIT,
• Hid,
• he,
• Him,
• i,
• hie,
• His,
• hip,
• Ht.,
• H,
• bi-,
• h's,
• hg.

The plural form of the word "hi" is "his"

The singular form of the word "hi" is "hi".