1. 祈祷；祷告
    Prayer is the activity of speaking to God.

    e.g. They had joined a religious order and dedicated their lives to prayer and good works...
           他们已加入一个宗教团体，终生都将祈祷和行善。
    e.g. The night was spent in prayer.
           整个晚上都在祷告。

2. 祈祷文；祷词
    A prayer is the words a person says when they speak to God.

prayer的解释

    e.g. They should take a little time and say a prayer for the people on both sides.
           他们应该花点时间，为双方的人祈祷。
    e.g. ...prayers of thanksgiving.
           感恩节祈祷文

3. 祈求的事；祈望
    You can refer to a strong hope that you have as your prayer .

prayer在线翻译

    e.g. This drug could be the answer to our prayers.
           这种药或许可以满足我们的祈望。

4. 祈祷仪式
    A short religious service at which people gather to pray can be referred to as prayers .

    e.g. He promised that the boy would be back at school in time for evening prayers.
           他保证男孩会及时回到学校参加晚祈祷。
    e.g. ...Muslims attending prayers in the main mosque.
           在大清真寺参加祈祷的穆斯林

5. 不可能成功
    If you say that someone hasn't got a prayer, you mean that it is impossible for them to succeed in what they are trying to do.

    e.g. She'd been caught from behind and hadn't a prayer of freeing herself.
           有人从后面抓住她，她不可能脱身。