1. 开始,着手：enter into 进入;参加;开始从事 | enter upon 开始,着手 | equip with 装备,配备
2. 开始：enter up 登记 | enter upon 开始 | Enter 输入
3. 开始着手做某事：The teacher enters him for the examination. 老师帮他报名参加了比赛. | enter upon 开始着手做某事 | The president has just entered upon another term of office. 总统刚刚开始另一个任期.
1. The treaty is a vital step towards a new global UN deal to be agreed upon in 2015 and to enter into force from 2020.
2. You wait a few minutes, and then take it upon yourself to enter the empty aircraft.
3. It also invites guests to enter a lottery upon entering the pavilion.
4. Many people may feel their lives intruded upon when people enter public places with their guide dogs.