It was difficult being in a foreign country, ________ if you don’t speak the language.
The disease failed to _______ to the new drugs the doctor used.
The experiment, though they had tried their best, ________ to be a failure.
Mr. White promised that he would tell me the result _______ he knew it.
We waited for her for a long time, and it was getting late when she finally _________.
【原创】I caught the last bus from town, but Harry came home___________ that night.