We may find that learning a foreign language does not have to be________learning our mother tongue,but can in fact be twice ________.
— Would you open the window , please ? — Yes , I ____ .
I''m surprised that he ____ to help me when I needed his help .
A lion ____ only attack a human being when it is hungry .
If you ____ me , I''ll give you some advice .
Although he knew little about the large amount of work done in the field, he succeeded ________ other more well - informed experimenters failed.