Until - правильный ответ. Мы продолжим расследование, пока не найдём убийцу.
There is an apple in the fridge.
We do not much sugar
Do we need many mangoes for the fruit salad
3)much
4)???
5)much
It is difficult to be a parent.
It is dangerous to swim along if you can't swim.
It is impossible to breath under the water.
It is stupid to sing in midnight.
It is boring sitting along all day.