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1.11. Exercises HYPERLINK /thinkCSpy/ch01.html \l exercises \o Permalink to this headline ? Write an English sentence with understandable semantics but incorrect syntax. Write another English sentence which has correct syntax but has semantic errors. Start a Python shell. Type 1 + 2 and then hit return. Python evaluates this expression, prints the result, and then prints another prompt. * is the multiplication operator, and ** is the exponentiation operator. Experiment by entering different expressions and recording what is printed by the Python interpreter. What happens if you use the / operator? Are the results what you expect? Explain. Type 1 2 and then hit return. Python tries to evaluate the expression, but it can’t because the expression is not syntactically legal. Instead, it prints the error message: File stdin, line 1 1 2 ^ SyntaxError: invalid syntax In many cases, Python indicates where the syntax error occurred, but it is not always right, and it doesn’t give you much information about what is wrong. So, for the most part, the burden is on you to learn the syntax rules. In this case, Python is complaining because there is no operator between the numbers. See if you can find a few more examples of things that will produce error messages when you enter them at the Python prompt. Write down what you enter at the prompt and the last line of the error message that Python reports back to you. Type print ‘hello’. Python executes this statement, which has the effect of printing the letters h-e-l-l-o. Notice that the quotation marks that you used to enclose the string are not part of the output. Now type hello and describe your result. Make note of when you see the quotation marks and when you don’t. Type print cheese without the quotation marks. The output will look something like this: Traceback (most recent call last): File stdin, line 1, in ? NameError: name cheese is not defined This is a run-time error; specifically, it is a NameError, and