21£®Known to be one of the most favorable environments for fossil preservation, the bones of many animals.
A£®volcanic areas have protected B£®to protect volcanic areas
C£®where volcaic areas have protected D£®volcanic areas which protect
22£®Keep in mind that you should do the same things in the instructions.
A£®as are listed B£®which are listed C£®as listed D£®that listed
23£®Unable to move because of the injury in his leg, Jack was foreed to wait he was, wrapped in Michael’s jacket.
A£®who B£®where C£®what D£®when
24£®—What will you buy for your husband’s birthday?
—I want to buy a wallet for him.
A£®black nice leather small B£®nice small black leather
C£®nice small leather black D£®small black nice leather