_______ in the 1800s and first mass-produced in Germany, the harmonica(口琴) was designed to play simple folk tunes.
#96728
A
Being invented
B
Inventing
C
Invented
D
Having invented
推荐题目
Our school, _____ in 1943, will celebrate its 70th anniversary this year.
#90900
A
founded
B
founding
C
to be founded
D
was founded
Neil Armstrong was the first man ______ on the moon in July 1969.
#94250
A
landing
B
landed
C
to land
D
lands
Henry always forgets things he has done. Yesterday he forgot__________ and looked for it everywhere.
#96752
A
to post the letter
B
to have the letter posted
C
to have posted the letter
D
having posted the letter
Properly _______ with numbers, the books can be easily found.
#97433
A
marked
B
mark
C
to mark
D
marking
_______to improve the students’sight, the eye exercises are done in schools nationwide.
#94304
A
Being designed
B
To design
C
Designing
D
Designed