One-third of the area ________ covered with trees. About seventy percent of the trees _______ been planted recently.
— Who dares to go ? How about you ? — Sorry , I ____ .
It''s nearly seven o''clock . Jack ____ . be here at any moment .
Johny , you ____ play with the knife , you ____ hurt yourself .
— ____ he be at home now ? — No . he ____ not . He ____ be in his office . He often goes home from work at almost twelve .
“That VCD you bought ____ very expensive” . “Do you know ____ ? ”