1.after two-year practice,he does well in typing(改为同义词)

1.after two-year practice,he does well in typing(改为同义词)
after two-year practice,he becomes an _expert__ __in_ typing
2.robert still stays in Japan(改为否定句)
Robert ___doesn't__ stay in Japan
3.my mother usually helped me with my homework during the primary time (改为同意句)
4.my mother _used__ _to__ _help___ me with my homework during the primary time

1.
after two-year practice，he becomes an expert on typing.
2.
Robert doesn'tstay in Japan
3.
my mother used to help me with my homework during the primary time

expert in
doesn't
used to help