"All his efforts were a little avail" ,"All his efforts were

这句英语 all his efforts to escape where to no avail. All these efforts were in vain..是啥子意思? He devoted all his efforts __ children.A.to educating B.educ i'm afraid all my efforts were in vain为什么用过去式 i am afraid all of my efforts were in vain.这句话的主谓宾是什么? I regret saying that all my efforts were in vain.如何改错句? All the people____at the party were his supporters.A:present make all effort 还是efforts? All the people present were impressed with his speech about New post,all from scratch,unremitting efforts 帮帮我啊exercise all reasonable efforts All his attempts were vitiated by his lack of will power.