15. It's already 10 o' clock. I wonder how it_________ that she was two hours late on such a short trip..
I’d like to know the way you succeeded in the experiment.
"Not all of the snakes were dangerous." this means _________.
It was not until midnight _________ his father came back.
________ she has made up her mind, nothing can change it.
It is always difficult being in a foreign country, _________ if you don’t speak the language.