UNIT SIX I HAVE FIFTY MARKERSLesson 21,New words,七十,seventy,八十,eighty,九十,ninety,Listen, look and learn,Lets learn,Who can guess the missing number,Who can guess the missing number?Its so easy! Two minus one is one,2-1=1,Who can guess the missing number?Its so easy! Three minus one is two,3-1=2,Who can guess the missing number?Its so easy! Three minus two is one,3-2=1,Who can guess the missing number?Its so easy! Thirty minus twenty is ten,30-20=10,Who can guess the missing number?Its so easy! Th
