Most birds find it safe to sleep in the trees, but ______ they have eggs or young chicks, they don’t use a nest.
A. why B. how C. where D. unless
---It’s getting dark, but Mr. Johnson is still at his office.
---No surprise. Who else can ______ he does?
A. do less work than B. work as hardly as
C. work as hard as D. be working hardly like
Since David ______ downloaded a virus into his computer, he can not open the file now.
A. readily B. accidentally C. horribly D. irregularly
---How often do you eat out?
---______, but usually once a week.
A. Have no idea B. As usualC. It depends D. Generally speaking
--Have the police found the parents of the baby found by the road?
---Not yet. His identity ______.
A. would be found out B. has been found out
C. is being found out D. had been found out
---Mr. Smith, ______ he have all these letters typed for you right away?
---He ______. They should be ready by 10 o’clock this morning.
A. will; must B. shall; has to C. need; will D. would; ought to
