Điền 1 từ thích hợp vào chỗ trống để hoàn thành đoạn văn:  On Mother's Day  sons and daughters visit their mothers and bring _______(1) flowers and little presents. The eldest son must ______(2) his mother a good cake. If sons or daughters cannot be_______(3) their mother on that day, they usually_______(4) her presents.  Mother's Day must be a day of rest_______(5) the mother of rest_______(6) the mother of the family, so her daughters_______(7) and the sons help to _______(8) the plates and dishes after dinner.  In the United States and Canada, Mother's Day is the second Sunday in May. They have a _______(9) beautiful stamp for Mother's Day in the United States.