换发球的英文：
[Sports] change of service
n. 体育运动
v. 故意显示；引人注目地穿戴；嬉戏
- sports decisiveness
运动果断性 - It was very sporting of you [You were very sporting] to keep it a secret.
你守住该秘密,很有运动员的风度[是承担一定的风险的]。 - junior sports development
青少年体育发展
n. 变化；交换，交替；零钱
v. 改变；交换，替换；兑换；更换
- change a bed;change the baby.
换床单；给婴儿换尿布 - We propose 'a change [making a change / to make a change / that a change should be made].
我们建议应做一点改变。 - The change of quantity can causes the change of quality.
量变可以引发质变。
n. 公共服务系统；公共事业机构；政府机构；帮助，效劳
v. 检修，维修；为…提供服务
- overhand service
高手发球 - take service with
在￥帮佣 - express goods service
特快货运业务