What is the difference between logical statements and statement variables?

Question

For the following two question

Let P, Q, and R be logical statements. Use a truth table to prove that_______.

Let P, Q, and R be statement variables, and suppose that the logical expression_______ is false.

The blank is two expressions which I don't know how to type those symbols, hope it doesn't matter.

Answer 1

Statement variables are atomic statements, i.e. statements with no connectives in them. Statement variables are usually written as letters $p, q, r, \ldots$.

Logical statements are any statements composed of statement variables and, possibly, connectives. For example: $p$, $\neg p$, $p \land q$, $(q \lor p) \to (r \lor q)$, $\ldots$.

Every statement variable makes for a logical statement, but not every logical statement is a single statement variable.

Answer 2

A logical statement like $P$ is meant to be a specific statement. For example, $P$ could mean 'It is raining'.

A statement variable is something we use to indicate that we are dealing with some statement ... but we don't know what it is.

It is like the difference between $2$ and $x$ when doing algebra. The $2$ is a specific number, but the $x$ is some unknown number.