As is known to all language learners, the newly learnt words will soon be forgotten unless ______ used in everyday communication.

The farmers are in bad need of rain,but a (an)          large amount of rainfall will cause Floods.

Although the new road is being used, it has not yet been _______opened.

There are forty five students in our class, and they are _____ interested in football.

 --- You've finally figured out the puzzle！--- Yeah, in a complex way, _______.