1.Many_inventors__in ancient china_invented__a lot of important_inventions____(invent)
2.Abacus is a_calculating___machine to do__calculation____,that is,abacus ia a kind of__calculator__(calculate)
3.The superman ia a very_powerful___man in our imagination(power)
4.Five_multiplied__by nine equals forty-five.(multiply)Five_times_nine is forty-five(times)
5.__Thousands_of people are spending their holidays in this little city.(thousand)