It began to be in use in 1998.
或It began being in use in 1998.
或It started to be in use in 1998.
或It started being in use in 1998.
四个都行.
但要注意不能是It began to be used in 1998.之类的,因为改写有一条原则：不改变原句中任何不需要改动的东西.虽然be in use和be used是一个意思,但为了遵守改写的原则,因而不能改动.