My favorite TV series My favorite TV series is Friends. It’s an relatively old series but I still enjoy it. It’s generally a comedy, but it literally moves me sometimes. I am totally attracted by the friendship among the characters. Also, I have learned some slang from it. I have memorized some useful expressions so that I can speak more naturally with native speakers.

Can I say: He has paid tremendous effort in his research? Can I say: "He has paid tremendous effort in his research." "He has buried himeself in his research." What else can I say to express "pay tremendous effort to something"?