Have you ever met with this case in your life you can't understand others even if they have said something several times？
| A．where | B．what | C．that | D．which |
I don't skate now, but I___________ when I was a kid.
| A．used to | B．am used to it | C．sued | D．used to do |
We liked the oil painting better____________ we looked at it.
| A．as | B．while | C．the | D．the more |
We must keep our room clean. Dirt and disease go ____________, you know.
| A．from time to time | B．hand in hand |
| C．step by step | D．one after another |
--Could I use your bike, Jack?
--Of course, you____________.
| A．can | B．may | C．could | D．might |
Helen is much more kind to her youngest child than to the others,___________ of course, make the others unhappy.
| A．who | B．which | C．she | D．that |