When Helen saw her tutor nod _______ to her, she calmed down and went on with her performance．

Since Tom ______ downloaded a virus into his computer, hecan not open the file now.

– I’m sorry for what I said. -- Forget it, I can’t remember _________.

It’s always difficult being in a foreign country, ________ if you don’t speak the language.

. It’s true that he did write some excellent poems, but he is ______ known as a playwright.