vt.

1. 进入
   He entered the classroom.

   他进了教室。

2. 参加；加入
   The United States did not enter the war until April 19, 1917.

   美国直到一九一七年四月十九日才参战。

3. 使参加；使进入
   They entered their child at a private school.

   他们让他们的孩子在一所私立学校就读。

4. 开始从事；开始进入
   He entered politics at the age of 30.

   他三十岁开始从政。

5. 登录；将……输入
   He showed me how to enter data into the computer.

   他告诉我如何将数据输入计算机。

vi.

1. 进入
   He rose as she entered.

   他在她进来时站起身来。

2. 参加，加入[（+for）]
   He decided not to enter for the race.

   他决定不报名参加比赛。

v.

1. come or go into (a place).
   ▸penetrate:

   the bullet entered his stomach.
   ▸ (enter on/upon) Law  (as a legal entitlement) go freely into (property) as or as if the owner.
2. (often enter into) begin to be involved in.
   ▸ (enter on/upon) begin (an activity or job).
   ▸join (an institution or profession).
   ▸register as a competitor or participant in.
   ▸register (someone) in a competition or examination.
   ▸ (enter into) undertake to bind oneself by (an agreement).
3. write or key (information) in a book, computer, etc.
4. Law  submit (a statement) in an official capacity, usually in a court of law.