The particles 呢 (ne) and 吗 (ma) are extremely common in Chinese. This article explains the two particles for beginners.

呢 and 吗 are similar in the following ways:

Both go at the end of a sentence.
Both of them can form questions.
Both of them are pronounced in neutral tone.
But these two particles have different uses:

吗 is used to turn statements into yes-no questions.
呢 is mostly used to turn statements into queries (amongst other things).
Now let’s look at the two particles in detail.