“Razorwife” wrote, “I just heard for the first time in my life that you can’t use ‘because’ at the beginning of a sentence. True or false?”

False. It’s OK to start a sentence with “because“; you just have to make sure you’re writing complete sentences and not sentence fragments.

“Because” heads up subordinate clauses, which means if you have a clause that starts with “because,” you must also have a main clause in your sentence. A main clause is something that could be a complete sentence by itself. The main clause can come first or last; if it comes last, you need a comma.

•  Because Squiggly woke up late, he had to postpone the fishing trip. (subordinate clause first, note the comma)
•  Squiggly had to postpone the fishing trip because he woke up late. (subordinate clause second, no comma needed)
•  Because he woke up late. (sentence fragment)