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b.   If the mangoes are not there, you will make cold coffee.

                     Here the condition is the availability of mango:
                     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 LOOP 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.



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