It depends on how "sex" in intended.
If you are using "sex" as a synonym for "gender", i.e. "The sex of this person is female", then the Arabic is Jens (جنس)
If you are using "sex" to describe human copulation in a positive way, i.e. "The husband and wife had sex", then the Arabic is also Jens (جنس)
There are a multitude of terms for negative conotations for sex, but to avoid cursing (per site guidelines) they will not be provided.
If you want to say Arabic in Arabic this is how you say it=Arabi
In Arabic we say Ramadan.
kabid
To say 'disbeliever' in Arabic, you would say 'kaffir.'
With is مع in Arabic.
To say "dessert" in Arabic, one would say "halwaa" which is spelled in the Arabic alphabet as حلوى.
In formal Arabic, say "Ayna Tareq?" In slang Arabic, say" wean Tareq?" or "Fean Tariq?"
أي كيو Its how to say IQ in Arabic
khasir........to say losers in arabic.......it is khasiroon
This is how you say "are you awake?" in Arabic: Inty suhya?
The way to say pear in Arabic is kumethra.
The way to say pear in Arabic is kumethra.