Answers

How come/John/so tired? (hint: you need a verb) How come John is so tired?

How come/so windy/today? (hint: you need to add a pronoun and a verb) How come it is so windy today?

How come/the sky/blue? How come the sky is blue?

How come/vending machine/out of order? How come the vending machine is out of order?

How come/coffee/so weak? How come the coffee is so weak?

How come/tea/so watery? How come the tea is so watery?

How come/trip/booked up How come the train is late?

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