Notes here based on Peace Corps China Lesson 3.
Pointing to something and naming it.
是 shì is “to be”. It is normally followed by a noun which defines the topic or subject. It is not normally followed by an adjective on its own.
| 这是茶。 | Zhè shì chá. | This is tea. |
| 那是饭。 | Nà shì fàn. | That is rice. |
Asking a yes-no question about something.
Add the question particle 吗 ma to the end of the sentence that would otherwise be a plain statement.
| 这是茶吗？ | Zhè shì chá ma? | Is this tea? |
| 那是饭吗？ | Nà shì fàn ma? | Is that rice? |
To respond, use 是 shì or 不是 bú shì. 不 bù is a negative word. It can mean “no” on its own, or it can negate the verb or adjective it precedes. (When it comes before a fourth tone, its tone changes to the second. Why?)
| 是。 | Shì. | Yes (it is). |
| 不是。 | Bú shì. | No (it isn’t). |
Asking what something is.
Use 什么 shénme, “what”. Like all Chinese interrogative pronouns, it goes in the position of the sentence where the answers would be expected.
| 这是什么？ | Zhè shí shénme? | What is this? |
| 这是茶。 | Zhè shì chá. | This is tea. |
| 那是什么？ | Nà shì shénme? | What is that? |
| 那是饭。 | Nà shì fàn. | That is rice. |