chuyen thanh thi phu dinh va nghi van

1.they were in Rio last summer

2.we did our exercise this morning

3.my parents came to visit me last July

4.the hotel was very expensive

5.i had a bicycle when i was young.

6.the children went to the zoo last Sunday

7.Ernie ate the last doughnut.

8.they bought a new house last month

n chia hết cho n-2

n+7 chia hết cho (n+1)

21 chia hết cho 2n+5

2n+7 chia het cho 2n+1

lấy một vài ví dụ về cách sử dụng trang phục không đúng cách

x là số nhỏ nhất sao cho x+14 chia hết 7, x-16 chia hết 8, 54+x chia hết 9.