We cannot figure out _______ quite a number of insects, birds, and animals are dying out.
She said the foreigners __ our city.
Don’t come at ten o’clock tomorrow, he ___then.
By the time the new pupil ___ enough courage to raise his hand, the bell__ for the end of the lesson
My family and I __ our New Year’s Eve dinner when the news of the outbreak of the war __ over on the radio.
How can you ___ if you are not ___?