So far we have done a lot to build a low-carbon economy, yet it is still _________ ideal. We have to work even harder.
Tom failed ______ the experiment yesterday.
I feel it an honor ______ to speak here.
Japan is an ______ industrial country.
---Who were those people with the banner? ---A group ______ itself the League for Peace.
---What's made Ruth so upset? --- ______ three tickets to the folk music concert.