Sustainable development is long-term ________which focuses on the environment and ________ natural resources.
Helen was much kinder to her youngest son than to the others, __________, of course, made the others envy him.
The English play __________ my students acted at the New Year’s party was a great success.
Only when your identity has been checked__________.
No sooner____ on my comfortable bed______ my telephone rang.
—Were you caught in the rain yesterday? —Good luck. No sooner home than it poured down.