Write the following phrase as a variable expression. Use $\mathrm{x}$ to represent "a number". a number less nineteen A number less nineteen is

Step 1 ：Write the following phrase as a variable expression. Use x to represent 'a number'.

Step 2 ：A number less nineteen is

Step 3 ：The phrase 'a number less nineteen' can be translated into a mathematical expression by replacing 'a number' with a variable, in this case, x. The word 'less' in mathematics usually means subtraction. So, 'a number less nineteen' can be translated into the expression 'x - 19'.

Step 4 ：Final Answer: The variable expression for the phrase 'a number less nineteen' is \(\boxed{x - 19}\)