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In such situations we use conditional blocks. Scratch has two conditional blocks. They are:
1. If…then block: In this block if the condition is true, the blocks inside conditional block will
run. If the condition is false, the blocks inside conditional block will not run. Then the blocks
outside the conditional block will run.
2. If…then…..else block: In this block if the condition is true, the blocks inside then condition
will run. If the condition is false, the blocks inside else condition will run.
For example, if the number you entered is less than 50, the sprite will turn 15 degrees to the right
otherwise, the sprite will move 20 steps backward.
i + USE OF LOOPING CONTROL BLOCKS
All the programs or projects you have developed till now run only once. If you want to run a set
of statements more than once, you will either run the code again or write the script again. In
Scratch, we can save our time and effort by repeating the code without writing the program or
script again. The automatic running of a set of instructions more than once is called looping. The
blocks for looping are given in Control category.
The Repeat block is used to run a set of instructions for a specified number
of times.
The Repeat Until block is used to run a set of instructions until a condition
is satisfied.
The Forever block is used to run a set of instructions continuously until
stopped. The instructions inside this block will be executed in a loop until the
Stop button is clicked by the user.
The Repeat and Repeat Until blocks can be used to display the multiplication table of a number
input by the user. The script for the sprite can be like this (using Repeat Until block).
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Scratch Programming—Game Creation

