I saw him _____ behind the tree, thinking.
| A．sat | B．seated | C．seating | D．seat |
Jumping out of ______airplane at ten thousand feet is quite _____exciting experience.
| A．/ ；the | B．/ ；an | C．an；an | D． the ; the |
What they need ______ enough money, while what we need ______ enough workers.
| A．is; is | B．are; are | C．is; are | D．are; is |
– Do you know William failed the exam, Jenny?
-- _____? As far as I know, he is always working hard.
| A．So what | B．How come | C．Why not | D．What for |
When you communicate with people, it is not unusual to find yourself in a situation ____ you have to politely decline an offer.
| A．where | B．which | C．what | D．why |
Not until Betty got to the airport _____ she had lost her tickets.
| A．that she realized | B．did she realize | C．where she realized | D．she realized |