If the building project______by the end of this month is delayed,the construction company will be fined.
Unfortunately, the research was limited __________ increasing economic profits, _________ protecting the environment.
We have to realize: boys share activities, _________ girls share feelings.
---- Pity you missed the lecture on nuclear pollution. ---- I _________ it, but was busy preparing for a job interview.
The most important thing about my job is ______ I help protect ordinary people from the volcano.
Everyone here will thank the firefighter for the things they have done to prevent fires______ the environment safer.