6.The boss asked his secretary to go to a concert and she ______ his invitation with pleasure.
A. received
B. accepted
C. rejected
D. refused
7.This tool machine is capable ______ being improve
D.
A. to
B. in
C. with
D. of
8.We ______ very close，but things have changed recently.
A. used to be
B. are used to being
C. are used to be
D. were used to being
9.He found it difficult to make himself ______.
A. understood
B. be understood
C. understand
D. to understand
10.It rained hard yesterday， ______ prevented me from going to the park.
A. that
B. which
C. as
D. it
