How come I can't bold the font that starts on a new line?

I am currently using the newer, updated version of Pages on a MacBook Pro non-Retina Display running OS X Mavericks 10.9. Whenever I start a new line in Pages, I can't immediately start typing in bold font. I have clicked the bold "B" button and have tried using the keyboard shortcut Command-B, but Pages just refuses to go into bold mode. Instead, I have to type what I want to say, highlight it, and then click bold, which is a waste of time. Is this just a bug or is it something I am not doing right?