Conditional statements are fundamental in programming as they allow you to execute different code blocks based on certain conditions. In Control Language (CL), conditional statements help control the flow of execution, making your programs more dynamic and responsive to different situations.

1. IF Statement: Executes a block of code if a specified condition is true.
2. ELSEIF Statement: Provides an additional condition if the initial IF condition is false.
3. ELSE Statement: Executes a block of code if none of the preceding conditions are true.
4. DO and ENDDO: Used to group multiple statements within a conditional block.

The IF statement checks a condition and executes the following block of code if the condition is true.

The ELSEIF statement provides an alternative condition if the initial IF condition is false.

The ELSE statement executes a block of code if none of the preceding conditions are true.

The DO and ENDDO statements are used to group multiple statements within a conditional block.

Explanation:

• The program declares a variable &AGE and sets its value to 25.
• The IF statement checks if &AGE is greater than or equal to 18.
• If the condition is true, it sends a message "You are an adult."

Explanation:

• The program declares a variable &SCORE and sets its value to 85.
• The IF statement checks if &SCORE is greater than or equal to 90.
• If the condition is true, it sends a message "Grade: A".
• If the first condition is false, the ELSEIF statement checks if &SCORE is greater than or equal to 80, and so on.
• If none of the conditions are true, the ELSE statement sends a message "Grade: F".

Task: Write a CL program that categorizes a person's age into "Child", "Teenager", "Adult", or "Senior".

Solution:

Task: Write a CL program that checks the temperature and sends a message indicating "Cold", "Warm", or "Hot".

Solution:

• Missing ENDDO: Ensure every DO block has a corresponding ENDDO.
• Incorrect Condition Syntax: Double-check the condition syntax, especially the comparison operators.
• Uninitialized Variables: Always initialize variables before using them in conditions.

In this section, you learned about conditional statements in CL, including the IF, ELSEIF, and ELSE statements, as well as how to group multiple statements using DO and ENDDO. You also saw practical examples and exercises to reinforce your understanding. Mastering conditional statements is crucial for controlling the flow of your CL programs and making them more dynamic and responsive. In the next section, we will explore looping constructs to further enhance your programming skills.