51 (   )

50. The grandson makes a lot of noise as (   ) .

• A、he never cares whether the neighbors might want to live in peace and quiet

• B、 the walls of the building are thin

• C、he likes to listen to his radio early in the morning

• D、friends come to visit him

4. (   )

• A、if

• B、of

• C、loaf

• D、 grief