Complete these sentences with the right form of these verbs
( get , become , change , rise , improve )
1,The number of people of the world ............. very fast.
2, He is still ill but he ........... better slowly.
3,These days, food ............ more and more expensive.
4,The world ................ Things never stay the same.
5,The cost of living .......... Every year things are dearer.
6,George has gone to work in Spain .When he arrived , his Spanish wasn't very good but now it ...........................
7,The economic situation is already very bad and it .............. worse.