15. As Polly was riding on the train, she sensed that she was _____ by a tall man in a dark coat.
Tom has a (n) for language,while his sister is a born pianist
— Let’s go to a movie after work, OK?— ___________. I am free tonight.
Thanks to the heavy rain, the football match _____ until next week.
I don’t agree with you two. I prefer______ a new car rather than______ it.
It was not until he arrived at the office_____ realized he had forgotten the key.