un demi
One half in French would be demi.
Half past in French is demie. If you wanted to say half past one in French you would say: Il est une heures et demie. It is one hour and half. Half past one. I have put the French way at the top, the complete translation in the middle and then the English way at the end.
"une demi-soeur"
et demi
in football a cntre half would be 'un milieu de terrain' in French.
"mi-trimestre"
"mi-trimestre"
Demi-journées
demi-frère
On se verra à une heure trente
Nos encontraremos en una y treinta
In French, you would say "Il est quatre heures et demie."