11: ____________ the experiment several times, the scientists finally succeeded in developing a new
vaccine.
A. Having carried out B. Have been carried out
C. Have carried out D. Have been carrying out
GẤP LẮM RÙI CẢ NHÀ ƠI, CÍU EM VỚI
11: ____________ the experiment several times, the scientists finally succeeded in developing a new vaccine. A. Having carried out B. Have been carrie
By Charlie
C11:
A.Having carried out
Chúc bạn học tốt
11: ____________ the experiment several times, the scientists finally succeeded in developing a new vaccine.
`text{Đáp án:}`
`text{A. Having carried out}`