There are several ways to say “able to” in Mandarin Chinese, depending on whether the meaning is a skill, ability, or permission.

Kěyǐ is used when asking permission, or when suggesting an alternate solution or method. It is also used to say “OK.”

Kěyǐ is made up of two characters: 可以. The first character 可 (kě) means "can,” or “may” and the second character 以 (yǐ) means “according to.”
Examples of Keyi
 

    Lǎoshī, wǒ xiànzài kěyǐ zǒu ma?
    老師, 我現在可以走嗎?
    老师, 我现在可以走吗?
    Teacher, may I leave now?

    Wǒmen bù kěyǐ jiǎng.
    我們不可以講｡
    我们不可以讲｡
    We are not allowed to speak.