66.Through/ Via mobile payment systems including WeChat and Alipay.
67. Because it will not take up his time and people go to flower shops at any time.
68.They can find their answers through mobile apps/the Internet.
69. occasionally/(every)now and then/once in a while
Dear Sir or Madam，
I’m LiHua, chairman of the Student Union. In order to meet the coming National Games in TianJin, a Dragon Boat Race will be held by our school. On behalf of our school, I sincerely invite you to take part in it.
The Dragon Boat Race is scheduled to start on Aug 3rd and last for 3 days. It is to be held in the Haihe river, where audience along the river can have a perfect view of the competition. It is through the race that students can not only feel the charm of the traditional custom but also gain a further understanding of the strength of unity. At the same time, it’s a valuable chance to improve the communication between two schools.
We believe this activity will become a part of the most unforgettable experience of students. So we hope you will come. please inform us your decision before 20th July so that we can make more detailed arrangements in advance.