What do you think this Pseudocode would achieve if it were translated into an actual computer program?
The program would accept a variable from the keyboard called AGE. It would then test a CONDITION. The condition here is if AGE is greater than or equal to 18. If the age of the person is equal to, or greater than, 18, then the condition is TRUE and the program will tell the user they are old enough to join the army. Otherwise, the condition is NOT TRUE and the program will tell the user they are not old enough to join the army yet. You will not always have an ELSE section. Sometimes you only want to run a statement if a condition is TRUE, and there isn't an alternative statement to run if the condition is NOT TRUE.
Note the indenting in the IF statement. This tells you the statement that will run if a condition is TRUE or NOT TRUE 'belongs' to the IF or ELSE part of the selection construct.
We have now used two of the three programming constructs, with which you can write ANY program, in the same piece of pseudocode. We have used Sequence; collecting a value from the keyboard and then testing a condition in an IF statement. And we have used the actual IF statement itself which is a selection construct.