So far scientist have not ___ to successfully devise a ...

[ Modals ]

So far scientist have not ___ to successfully devise a mechanism

A. been able

B. need

C. must

Select your answer:
A B C D E

Other quiz:

Grammar › View

Do you like reading books?

A. Yes, I read

B. Yes, I like

C. Yes, I have

D. Yes, I do

Past Tense › View

The two kids ….. (make) the sandcastle two days ago.

A. make

B. makes

C. maked

D. made

Grammar › View

What is the correct abbreviation for October?
A. Octo.
B. Oct.
C. Oct
D. Octob.

Indefinite Pronouns › View

______ bought me a drink yesterday.

A. Something

B. Everybody

C. Someone

D. Somewhere