If you don't know any greeting phrases , then you can say aSalam alikoum to anyone in any time in any where
السلام عليكم
the greetings in Arabic language :
Good morning
صباح الخير
Sabaho alkhair
The meaning of " good " جيد gayd , but when useing it in greating the meaning be خير
Morning صباح
Good evening
مساء الخير
Masaao alkhair
Evening مساء
masaa
Good night
ليلة سعيدة
Laila Saida
Night ليلة
سعيدة mean happy
But using it in greatings the meaning be سعيد
I wish to you
أتمنى لك
Atmna lka
Sweet dreams أحلام سعيدة
Ahlam " s aa eda "
Dreams احلام
Sweet سعيدة
Sweet mean حلّو
But in that sentence meant سعيدة
Happy day
يوم سعيد
Yaom sa aa ed