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We can also write this in two ways:
                     1.  if                                           2.  if
                           mango is available                               mango is available
                         then                                             then
                           make the mango shake                             make the mango shake
                                                                          else

                                                                            make cold coffee
                      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 then or only inside
                   conditional block will run. If the condition is false, the blocks inside conditional block will not
                   run. Only 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.

                    Try out the following examples:
                    Suppose, we want to check whether a person is a senior citizen or not. The code for this can
                   be defined using if...then as:















                    But this code does not give an output if the age of the person is less

                   than or equal to 60 years. For such situations, when two different
                   outputs are to be specified for two conditions, we use the if…then…
                   else block. In this block, if the condition is true, the code inside the
                   first C (shape) will be activated. If the condition is false, the code
                   inside the second C (shape) will be activated.



                        USE OF LOOPS BLOCKS


                 All the programs or projects 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
                 again or writing the script again. The automatic running of a set of instructions more than

                 once is called looping. The blocks for looping are given in the Control category.
                 The repeat block is used to run a set of instructions for a specified number
                 of times.



                                                                                       Conditional Blocks in Scratch  107
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